# PGR + Cool Season Grass



## chrismar

The warm season folks have their thread, so should we start one for us cool seasoners?

*FAQs*

*Q: When should I start applying PGR?*
A: The general consensus is to start applying PGR after your 2nd mow of the season.

*Q: Does the above apply if I recently renovated?* 
A: Yep!

*Q: How often should I reapply my PGR?*
A: A lot of folks use the GreenKeeer App to help them estimate when your PGR needs to be reapplied. The GreenKeeper App takes your location, grass type, application rate and climate/weather into account to make it's recommendations. If you don't want to use the GreenKeeper App, every 3 weeks is the suggested re-application cadence.

*Q: How much PGR should I apply?*
A: It is recommended that you start low and work your way up. For example, using a PGR with Trinexapac-ethyl 11.3% as the AI, start with 0.3 to 0.4 oz / M (1,000 SF). If that gives you the regulation you desire, stay there. If not, increase it slightly on the next application.

*Q: Are there any risks associated with applying a PGR?*
A: You betcha! For starters, if you apply too much your yard will look FUGLY until it wears off, and you might experience some die-off. Additionally, if your lawn has some sort of disease/fungus the PGR can prevent the disease from growing out as quickly as it would if it weren't under regulation.


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## chrismar

I'll start with a q:

I'm planning to do my next PGR+ FAS this Thursday. Forecasted temps are in the upper 80s to perhaps 90. I think PGR is safe to apply at these temps (nothing is mentioned on the label), so my question is, what about FAS? Posts on other sites say to avoid FAS above 85. But why? Higher risk of burning?


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## j4c11

Now that I've been using it for 2 years, PGR is one of the things I wouldn't do lawn care without. I apply 0.35oz/K trinexapac every 2 weeks, and the benefits I've noticed are:
- Slows down growth and reduces the amount of mowing needed. When I do mow, there's far less clippings.
- Increases density, 
- Significantly enhances color. 
- Reduces seed heads
- Increases root mass
- Does wonders for me as far as drought resistance through the summer.

It's a jug of magic


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## j4c11

chrismar said:


> I'll start with a q:
> 
> I'm planning to do my next PGR+ FAS this Thursday. Forecasted temps are in the upper 80s to perhaps 90. I think PGR is safe to apply at these temps (nothing is mentioned on the label), so my question is, what about FAS? Posts on other sites say to avoid FAS above 85. But why? Higher risk of burning?


Yes, it can burn the grass. Having said that, you can spray it in the evening and do a quick rinse-off the following morning.


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## chrismar

I'm trying to find my magic. I applied .60 oz/K three weeks ago and my KBGs growth was barely regulated. I'm going to try .75 oz/K this week. I'm hoping to finally see a measurable impact.


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## j4c11

chrismar said:


> I'm trying to find my magic. I applied .60 oz/K three weeks ago and my KBGs growth was barely regulated. I'm going to try .75 oz/K this week. I'm hoping to finally see a measurable impact.


Are you applying with a surfactant? I find that makes a big difference.


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## chrismar

j4c11 said:


> Are you applying with a surfactant? I find that makes a big difference.


Yep, I did 1 Tbsp of a NIS / gallon (4 total in my backpack sprayer).


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## ericgautier

What brand(s) is everyone using?


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## j4c11

I use T-Nex 1AQ. Split a jug with another gentleman last year, a whole gallon would probably last me 5-6 years and there's a shelf life.


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## wardconnor

chrismar said:


> ...I'm planning to do my next PGR+ FAS this Thursday.....


What is your FAS source and what are you using? Are you using MQ's formula? I want to start spraying iron but need more info for cool season turf. MQ said to use his formula at half strength. Anyone have experience with this?


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## chrismar

I'm using "Prime Source Trin-Pac Select".


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## Mightyquinn

wardconnor said:


> chrismar said:
> 
> 
> 
> ...I'm planning to do my next PGR+ FAS this Thursday.....
> 
> 
> 
> What is your FAS source and what are you using? Are you using MQ's formula? I want to start spraying iron but need more info for cool season turf. MQ said to use his formula at half strength. Anyone have experience with this?
Click to expand...

I recommend starting at half rate for Rye and TTTF as I don't know how sensitive they are. I would start there and work your way up to full strength.


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## chrismar

wardconnor said:


> What is your FAS source and what are you using? Are you using MQ's formula? I want to start spraying iron but need more info for cool season turf. MQ said to use his formula at half strength. Anyone have experience with this?


I'm using powder/granular ferrous sulfate and ammonium sulfate obtained from ebay & amazon (respectively). I do 4 oz / K of ferrous sulfate and 3.4 oz / K of ammonium sulfate. This is the rate for KBG, I believe TTTF and mixes should use a lower rate.


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## wardconnor

Mightyquinn said:


> I recommend starting at half rate for Rye and TTTF as I don't know how sensitive they are. I would start there and work your way up to full strength.


Thanks MQ. I think that I will try that soon hopefully.


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## j4c11

Having done full strength applications last year, I actually recommend doing half rate apps every two weeks. With full apps you typically get about 3 weeks and then you have to spray again because it rebounds, whereas with half rate every 2 weeks you get 4 weeks of coverage on the same amount of PGR, so 30% more. The other advantage is if you overspray a spot at half rate, it's basically full rate, whereas if you over spray a spot at full rate it's double rate. The disadvantage is clear - for a 20 week growing season you're doing 10 rounds of spraying instead of 6-7 at full rate.


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## chrismar

j4c11 said:


> Having done full strength applications last year, I actually recommend doing half rate apps every two weeks. With full apps you typically get about 3 weeks and then you have to spray again because it rebounds, whereas with half rate every 2 weeks you get 4 weeks of coverage on the same amount of PGR, so 30% more. The other advantage is if you overspray a spot at half rate, it's basically full rate, whereas if you over spray a spot at full rate it's double rate. The disadvantage is clear - for a 20 week growing season you're doing 10 rounds of spraying instead of 6-7 at full rate.


It's difficult enough as it is for me to get the 6-7 sprays in. Adding another 3-4 sprays increases the likelihood it won't get done.


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## ericgautier

I'm on T-Pac E-Pro MEC (Trinexapac-ethyl 11.3%).

Rates I'm using:
KBG - .6 oz/k
TTTF+KBG - .75 oz/k

I'm on a 3 week interval schedule and can definitely tell that it is working.

I'm debating on doing 1/2 rates going into Summer.


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## Pete1313

What does anyone think about using Primo when establishing new grass? I'm planning to put down an app, if needed, on the reno to keep top growth under control so i can keep it mowed short. Would probably try an app after any bleaching from the tenacity post-m app wore off. Thoughts?


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## j4c11

I started with PGR about 60 days into my spring reno. So far so good.

Edit: I also spray fungicide with it. Young grass, fungus and PGR don't mix well.


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## Pete1313

j4c11 said:


> I started with PGR about 60 days into my spring reno. So far so good.
> 
> Edit: I also spray fungicide with it. Young grass, fungus and PGR don't mix well.


Thanks for the info. :thumbsup:


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## chrismar

Made my 2nd PGR+FAS app of the season. PGR was at .75 Oz/K since .60 Oz/K didn't seem to do all that much last time. I mucked up on my FAS calculation, though. Instead of 4 oz ferrous sulfate and 3.4 oz ammonium sulfate per K (gallon) I did 4/3.4 per 4k, so 1/4 of what I was supposed to do. Probably for the better considering the weather, but still bummed I won't get the full dose of the nice green up it provides.


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## LIgrass

Pete1313 said:


> What does anyone think about using Primo when establishing new grass? I'm planning to put down an app, if needed, on the reno to keep top growth under control so i can keep it mowed short. Would probably try an app after any bleaching from the tenacity post-m app wore off. Thoughts?


I had no ill effects on the small repairs I did using PGR on them this spring (KBG & PRG). If anything, it thickened them up faster.

I use T-Pac E-Pro MEC (Trinexapac-ethyl 11.3%) like ericg. I try to keep single apps at or under 0.5oz/K.


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## Pete1313

LIgrass said:


> I had no ill effects on the small repairs I did using PGR on them this spring (KBG & PRG). If anything, it thickened them up faster.


Awesome! Thanks for sharing! I am going to see how the renovation goes and try and work it into the plan in the fall. :thumbsup:


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## Pete1313

Figure I'll share this here. It was a question I sent off to Syngenta in September 2015. I wondered why the label shows lower rates on shorter turf.



Pete1313 said:


> I have a question about the application rates of primo maxx to Kentucky bluegrass. The label shows .6 fl oz/k for residential turf and .25 fl oz/k or fairways at .5" or less. My question is why the lesser rate on fairway heights? Is it because Primo maxx is more effective at lower heights of cut so less is needed to obtain the same results? Or is the turf at a lower height unable to handle a higher dose so less product sprayed more frequently is required? I'm currently maintaining Kentucky bluegrass between .75"-1.00" height of cut with primo applications at .6 fl oz/k every 3-4 weeks and looking to maintain it around .5" next year. Thanks for the support an great products!





Syngenta said:


> Hi Peter,
> 
> I consulted with a turf expert to answer your question. Here is the response:
> 
> Primo is generally more active on turf mowed at lower heights. The primary reason is thought to be at lower mowing heights, there is less leaf tissue to intercept the spray, so more product penetrates into the canopy and reaches the growing point. If he is bringing his mowing heights down to 0.5" next year, we would suggest starting at 0.25 oz per 1000 for 2 applications on 3 week intervals, then increase to 0.4 oz and adjust up or down from there.
> 
> Thank you for asking and have a great day!
> 
> Teresa
> 
> __________________________
> 
> Teresa Acosta
> Resource Rep
> Technical Services
> Syngenta


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## Ware

That's cool. Thanks for sharing.


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## Pete1313

Ware said:


> That's cool. Thanks for sharing.


No problem. Also, Syngenta is quick to respond to questions, even from us "little guys".


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## LIgrass

Good to know. Thanks for sharing!


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## Ware

Pete1313 said:


> Ware said:
> 
> 
> 
> That's cool. Thanks for sharing.
> 
> 
> 
> No problem. Also, Syngenta is quick to respond to questions, even from us "little guys".
Click to expand...

I just sent them a message about using a surfactant with Primo. :thumbup:


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## chrismar

.75 oz/K seems to be working much better. There's been some top growth, but nowhere near where it would be at day 7 without a PGR. Mowing Sunday, which will be day 9.


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## Togo

wardconnor said:


> What is your FAS source and what are you using? Are you using MQ's formula? I want to start spraying iron but need more info for cool season turf. MQ said to use his formula at half strength. Anyone have experience with this?





Mightyquinn said:


> I recommend starting at half rate for Rye and TTTF as I don't know how sensitive they are. I would start there and work your way up to full strength.


I've tried the a couple rates of FAS on my lawn which is a mix of PRG, Fine Fescue, KBG, and possibly a very little TTTF. I did the half rate the first time and really didn't notice much in terms of results. Maybe it was because it was my first time or too early in season. The full dose makes the lawn look great for the first day or so but then will be too much for the PRG/Fescue and it turns it a weird gray/black. It goes away after a few weeks but I've been experimenting at lower doses. The last rate was at 75% of full dosage and even that I found to be a bit strong after a couple days. I may try 66% of full next time I do it or I may just try 50% but at closer intervals. Either way, I know this, if you put down too much you will be able to tell quickly within a few days just by the blackness of the lawn.


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## chrismar

I must be doing something wrong, have a defective batch of PGR or my expectations are just out of control.

Here's a windrow and some clippings in my hand after 7 days:



















This seems like a lot of clippings for 5 weeks under PGR control and after 7 days without a cut. My last PGR app was 2.5 weeks ago. Making my third app later this week. The last app was at .75 oz/K.

Am I losing it, is my PGR not working or are my expectations out of whack?

(Yes, I know, my blades could probably use a sharpening...)


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## j4c11

Are you applying fertilizer?


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## chrismar

j4c11 said:


> Are you applying fertilizer?


I did 1/4 rate FAS at my last PGR spray (see a few posts up) and OceanGro was last spread on 6/18 at bag rate (15 lb/K, .75 lb/K N).


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## j4c11

That seems like a lot of growth to me for this time of the year even without PGR. Normally it should slow down because of the heat. It's almost as if your grass is jacked up on fertilizer.

Here's the best way to tell: mark out a square in a corner somewhere and don't spray it, spray the rest of the yard. It should quickly become apparent whether the PGR is suppressing growth or not.


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## chrismar

j4c11 said:


> That seems like a lot of growth to me for this time of the year even without PGR. Normally it should slow down because of the heat. It's almost as if your grass is jacked up on fertilizer.
> 
> Here's the best way to tell: mark out a square in a corner somewhere and don't spray it, spray the rest of the yard. It should quickly become apparent whether the PGR is suppressing growth or not.


Good idea. I'll rope off an area to to not spray when I re-apply later this week.


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## ericgautier

Good suggestion j4c11.

Not sure what is going on chrismar.. but my experience with PGR is definitely different than yours.


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## LIgrass

chrismar said:


> I must be doing something wrong, have a defective batch of PGR or my expectations are just out of control.
> 
> Here's a windrow and some clippings in my hand after 7 days:
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> This seems like a lot of clippings for 5 weeks under PGR control and after 7 days without a cut. My last PGR app was 2.5 weeks ago. Making my third app later this week. The last app was at .75 oz/K.
> 
> Am I losing it, is my PGR not working or are my expectations out of whack?
> 
> (Yes, I know, my blades could probably use a sharpening...)


Just curious and sorry if I missed it in the thread...where did you get your PGR? That looks like spring flush type growth.

I would measure the grass after cutting, and again 7 days later. Don't go by just the mower setting HOC. See what the results are.


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## chrismar

LIgrass said:


> Just curious and sorry if I missed it in the thread...where did you get your PGR? That looks like spring flush type growth.


I got it from Do My Own. This to be exact.



> I would measure the grass after cutting, and again 7 days later. Don't go by just the mower setting HOC. See what the results are.


Good idea. I'll do this in addition to leaving a section un-sprayed.


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## LIgrass

chrismar said:


> LIgrass said:
> 
> 
> 
> Just curious and sorry if I missed it in the thread...where did you get your PGR? That looks like spring flush type growth.
> 
> 
> 
> I got it from Do My Own. This to be exact.
> 
> 
> 
> 
> I would measure the grass after cutting, and again 7 days later. Don't go by just the mower setting HOC. See what the results are.
> 
> Click to expand...
> 
> Good idea. I'll do this in addition to leaving a section un-sprayed.
Click to expand...

I've read that PGR's can lose their effectiveness over the years. Maybe check the bottle date to see if that's a possibility. At 0.75 oz/K you should definitely be well-regulated. I target just over half that rate and get very little growth. Another possibility is what j4c11 said and maybe there's a lot of residual fertilizer that is kicking in with the heat now. The only other thing I could think is if you're lawn's getting an extraordinary amount of water. That could definitely cause growth like that.
Honestly though, if nothing changes with future apps, I'd call that company up and see if they can figure out what the problem is. Keep us posted. 
Just a funny side note: somehow this product is banned in 17 states but is for sale to NY .... something's DEFINITELY not right, lol. (I'm kidding, sort of)


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## chrismar

LIgrass said:


> I've read that PGR's can lose their effectiveness over the years. Maybe check the bottle date to see if that's a possibility.


I've read the same. I checked the bottle yesterday for dates. Outside of what looks like a lot number there's no date to be found.



> The only other thing I could think is if you're lawn's getting an extraordinary amount of water. That could definitely cause growth like that.


We have had a pretty wet summer. Wetter than I can remember in recent years. My irrigation controller has also been acting up, but I've been keeping in check by manually turning it on and off when I think the lawn or gardens need water.

We'll see how this latest experiment plays out. If I get little/no regulation this (3rd) time I'll be calling them up.

On a side note: Eric, maybe I can "borrow" a few ounces of your PGR for my next app to see if that works any differently?


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## ericgautier

chrismar said:


> On a side note: Eric, maybe I can "borrow" a few ounces of your PGR for my next app to see if that works any differently?


Sure man. I work in Bridgewater so, we can definitely meet up.


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## wardconnor

OK so I know that Andy would scream and yell about this question but he is not here so I want to ask. PGR mixed with 24D. Can I? I know I CAN do anything I want but sometimes doing what you want because you CAN is not always best. Thoughts


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## j4c11

wardconnor said:


> OK so I know that Andy would scream and yell about this question but he is not here so I want to ask. PGR mixed with 24D. Can I? I know I CAN do anything I want but sometimes doing what you want because you CAN is not always best. Thoughts


I don't know. 2,4D is a growth hormone and the PGR is a growth suppressor. How those two things will act when they both hit a weed, who knows.


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## RockyMtnLawnNut

This article seems to indicate that it can be done but that it causes greater turf injury.

http://caes2.caes.uga.edu/commodities/turfgrass/georgiaturf/WeedMngt/weedcontrol/PGR.htm


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## wardconnor

Thanks guys


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## GrassDaddy

haha maybe by next year we won't be afraid to ask these questions without a preface =P


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## chrismar

Sprayed PGR (no FAS) at .75 oz/K on Wednesday evening. Mowed today. Height right after mow: 4.5".


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## j4c11

chrismar said:


> Sprayed PGR (no FAS) at .75 oz/K on Wednesday evening. Mowed today. Height right after mow: 4.5".


Your mower blades really need sharpening :thumbup:


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## chrismar

j4c11 said:


> Your mower blades really need sharpening :thumbup:


I know. Maybe Sunday if my better half doesn't make plans for me.


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## wardconnor

chrismar said:


> Sprayed PGR (no FAS) at .75 oz/K on Wednesday evening. Mowed today. Height right after mow: 4.5".


 :thumbup: I like


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## social port

wardconnor said:


> OK so I know that Andy would scream and yell about this question but he is not here so I want to ask. PGR mixed with 24D. Can I? I know I CAN do anything I want but sometimes doing what you want because you CAN is not always best. Thoughts


What purpose did you have in mind? Just curious. I like the inquisitiveness and the experimental mindset.


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## wardconnor

social port said:


> wardconnor said:
> 
> 
> 
> OK so I know that Andy would scream and yell about this question but he is not here so I want to ask. PGR mixed with 24D. Can I? I know I CAN do anything I want but sometimes doing what you want because you CAN is not always best. Thoughts
> 
> 
> 
> What purpose did you have in mind? Just curious. I like the inquisitiveness and the experimental mindset.
Click to expand...

 I have some serious clover. In the back. It's really ticking me off. I just figure if I'm blanket spraying then why not get any weeds while at it.

I did it before I asked. The mix knocked the clover back but doubt it will kill it. I did not see any ill affects


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## chrismar

wardconnor said:


> I have some serious clover. In the back. It's really ticking me off. I just figure if I'm blanket spraying then why not get any weeds while at it.
> 
> I did it before I asked. The mix knocked the clover back but doubt it will kill it. I did not see any ill affects


Yea, in my experience clover laughs at 2,4-D. Triclopyr, now that's a a different story.


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## wardconnor

chrismar said:


> wardconnor said:
> 
> 
> 
> I have some serious clover. In the back. It's really ticking me off. I just figure if I'm blanket spraying then why not get any weeds while at it.
> 
> I did it before I asked. The mix knocked the clover back but doubt it will kill it. I did not see any ill affects
> 
> 
> 
> Yea, in my experience clover laughs at 2,4-D. Triclopyr, now that's a a different story.
Click to expand...

Yep. Clover is my archenemy.


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## chrismar

Mowed yesterday, 6 days after my last mow and 7 days since PGR.

Pre-cut grass measured at 5-6.5".










I don't think it's bad spraying technique, for two reasons:

1) The tall vs short blades are right next to each other.
2) The entire sprayed area is like this. Tall & short blades all in the same area. In other words, its uniform and all looks the "same" when not viewed from your hands and knees.

The after cut shows 4", in the same general area. Not sure why I was getting 4.5" last week. Maybe I was in a hole?










The un-sprayed test plot is unquestionably taller. By about an inch (guess, didn't measure, should have). It's easy to spot if you know where it is.

It's also embarrassing how dull my blades are. I need to make sharpening those a priority this weekend.


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## g-man

So the pgr is having an effect since the un tested was higher, correct? What about the next time create a section (in a back corner) double the rate in addition to the untreated area?


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## thegrassfactor

chrismar said:


> Mowed yesterday, 6 days after my last mow and 7 days since PGR.
> 
> Pre-cut grass measured at 5-6.5".
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> I don't think it's bad spraying technique, for two reasons:
> 
> 1) The tall vs short blades are right next to each other.
> 2) The entire sprayed area is like this. Tall & short blades all in the same area. In other words, its uniform and all looks the "same" when not viewed from your hands and knees.
> 
> The after cut shows 4", in the same general area. Not sure why I was getting 4.5" last week. Maybe I was in a hole?
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> The un-sprayed test plot is unquestionably taller. By about an inch (guess, didn't measure, should have). It's easy to spot if you know where it is.
> 
> It's also embarrassing how dull my blades are. I need to make sharpening those a priority this weekend.


PGRs do not have the equivalent effect on cool season turf as it does Bermuda. That being said, you can still shorten those nodes and tighten it up if you run say .6oz bi weekly until you observe desired regulation and then half it (.3 to .4oz) and continue to apply bi weekly. Optimally you would want to start this before the initial growth flush observed in spring. For us in Knoxville, that's late March. If you're doing it just for color and root mass, run it bi weekly at .6 to .7 oz with fungicide, ammonium sulfate, and any other macros/micros as determined by a soil test.

Try stepping your application frequency up to bi weekly and see how that influences growth


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## chrismar

g-man said:


> So the pgr is having an effect since the un tested was higher, correct? What about the next time create a section (in a back corner) double the rate in addition to the untreated area?


It is having some effect, but not the effect I was expecting. Folks describe barely cutting off anything after 9 days of growth. For me, I'm cutting .5-1.5" after 6 days of growth.

I can try a section of double the rate, but that's 1.5 oz/K. That seems really, really high.



thegrassfactor said:


> Try stepping your application frequency up to bi weekly and see how that influences growth


I don't think spraying PGR every other week is going to be possible. I already have a hard time getting out there every 3 weeks. PGR is supposed to make my life easier, not harder!


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## LIgrass

Here's my theory on this chrismar: We know that PGR's are more effective on shorter cut grass. I don't know the exact reasoning behind that but I would imagine less leaf surface area = less gibberellic acid production. That's why Syngenta advises to use less Primo on sub-1" turf. Anyway, since your control plot showed more growth we know the product is working to some extent. Maybe wait til you drop the HOC to see if the results change a bit. I wouldn't expect zero growth after 9 days though. It still grows, just at a much slower rate.


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## ericgautier

LIgrass said:


> Here's my theory on this chrismar: We know that PGR's are more effective on shorter cut grass.


This is what I was thinking also.

Just last week I increased the HOC to 3.5". I was at 3" for awhile.


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## j4c11

If you look at the first picture you a see a lot of boat shaped tips, meaning this is new growth that has never been cut. This is the same thing I have experienced with PGR on KBG. I started a thread on it earlier this year:

http://www.thelawnforum.com/viewtopic.php?f=9&t=283

In previous years with TTTF, the PGR effect was uniform. KBG definitely responds differently. My working theory is that this is new growth from spreading via rhizomes, or new tillers. These would have been beneath the 4" level when you sprayed the PGR and would not have been affected.

Unfortunately, there is always new growth coming up from underneath with KBG. You should however get a big reduction in the amount of clippings produced when mowing. The clippings issue was a big one for me, as it was making a huge mess.

Have you seen a boost in color from the PGR?


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## chrismar

j4c11 said:


> Unfortunately, there is always new growth coming up from underneath with KBG. You should however get a big reduction in the amount of clippings produced when mowing. The clippings issue was a big one for me, as it was making a huge mess.


Unfortunately I still get a ton of clippings. Nice little brown windrows. Looks terrible, actually.


> Have you seen a boost in color from the PGR?


The color has stayed a nice consistent green. Even through the peak of summer (so far). There's been some browning, from my duller than a spoon mower blades and summer stress, but still the greenest on the block.


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## chrismar

LIgrass said:


> Here's my theory on this chrismar: We know that PGR's are more effective on shorter cut grass. I don't know the exact reasoning behind that but I would imagine less leaf surface area = less gibberellic acid production. That's why Syngenta advises to use less Primo on sub-1" turf. Anyway, since your control plot showed more growth we know the product is working to some extent. Maybe wait til you drop the HOC to see if the results change a bit. I wouldn't expect zero growth after 9 days though. It still grows, just at a much slower rate.


I think I can agree with your hypothesis, and I understand what you're saying. But man, I'd be lyin' if I said I wasn't expecting more. Would you suggest I try an even higher rate since I'm cutting so tall? Maybe try 1 oz/K?


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## g-man

^ Hence why I think you should test a higher rate. Ideally we could design a full DOE (rate, hoc, frequency).


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## chrismar

g-man said:


> ^ Hence why I think you should test a higher rate. Ideally we could design a full DOE (rate, hoc, frequency).


Yea... I think I might try a blanket 1 oz/K instead of a small test plot of even higher. Much easier to keep straight in my head than "this test plot gets no PGR, this one gets double, this one gets .25 oz more", etc.


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## j4c11

I'm just shocked at how much the grass is growing for this time of the year.


----------



## chrismar

j4c11 said:


> I'm just shocked at how much the grass is growing for this time of the year.


Me too! I renovated in 2015, so this is 2nd full season of this grass. I always thought it was the first year it sleeps, the 2nd it creeps and the 3rd it leaps. I think I skipped over the creeping part. Or, if this is creeping I'm scared to see what leaping looks like!

Given how much it's been growing I haven't fertilized in almost a month and I haven't watered in almost 2 weeks. We have been getting some rain, about an inch over the last 2 weeks according to my rain gauge.


----------



## LIgrass

chrismar said:


> LIgrass said:
> 
> 
> 
> Here's my theory on this chrismar: We know that PGR's are more effective on shorter cut grass. I don't know the exact reasoning behind that but I would imagine less leaf surface area = less gibberellic acid production. That's why Syngenta advises to use less Primo on sub-1" turf. Anyway, since your control plot showed more growth we know the product is working to some extent. Maybe wait til you drop the HOC to see if the results change a bit. I wouldn't expect zero growth after 9 days though. It still grows, just at a much slower rate.
> 
> 
> 
> I think I can agree with your hypothesis, and I understand what you're saying. But man, I'd be lyin' if I said I wasn't expecting more. Would you suggest I try an even higher rate since I'm cutting so tall? Maybe try 1 oz/K?
Click to expand...

If you think your lawn will be ok with 1 oz. you could try it. That rate would definitely stress my Bewitched. I think when you drop the HOC you'll see better results though. If not, then there's something wrong with that particular product you have.


----------



## chrismar

Dare I say I saw some improvement this week? I mowed yesterday, 6 days after my last cut.

Pre-cut, PGR treated areas were at 4.5 - 5":










Pre-cut, non-PGR control area was at 7-8" (!!):










So, the PGR is working better this week. I'm guessing the lack of N, lack of water, summer stress + PGR are finally starting to slow things down. Guess it's good because I'll be back to mowing at least twice a week when the fall N process starts.


----------



## NJ88

What are the benefits and negatives of using a PGR in the fall season ?

Does the first app go down after the turf is in full recovery mode after summer heat ?


----------



## chrismar

Sprayed my PGR at 1 oz / K today. Hopefully that keeps things under control as I start the aggressive fall program in a few weeks. Also sprayed FAS at the maximum rate.


----------



## ABC123

People that use a pgr. Do you also put down a fungicide for a preventative measures or is it not needed all year?


----------



## chrismar

ABC123 said:


> People that use a pgr. Do you also put down a fungicide for a preventative measures or is it not needed all year?


I sort of did back in July. I made 2 apps of Bayer fungus control at the curiative rate. In retrospect I probably didn't need to. At the time I thought I saw some leisons on some blades, but I think what I saw was due to some missteps by my landscaper and just general bbdl (brown blades down low).


----------



## ericgautier

ABC123 said:


> People that use a pgr. Do you also put down a fungicide for a preventative measures or is it not needed all year?


I do/am on the preventive biofungicide regimen. I've been spraying Serenade every 2 weeks and so far so good. I did also drop the Bayer and Scotts fungicide as well though on some areas that needed it.


----------



## Colonel K0rn

I've created a thread in the Equipment Exchange subforum for people who want to participate in a PGR Group Buy. If you would like to participate in this, please check out the thread, and complete the form.


----------



## chrismar

chrismar said:


> Sprayed my PGR at 1 oz / K today. Hopefully that keeps things under control as I start the aggressive fall program in a few weeks. Also sprayed FAS at the maximum rate.


1 oz / K seems to have done the trick. I'm cutting about once every 6-7 days now, which is much better than every 4-5. days. I made it to 8 days between cuts last week and there weren't any windrows or large amounts of visible clippings. Of course it could also be the less frequent rain and irrigation. Either way, I'll take it.

I'm going to let it come out of regulation now, though. I'm seeing some fungusy looking blades and I'm hoping the aggressive urea apps + the cooler weather push out whatever it is. I know I'll be mowing every 3-4 days, but I want to kick out whatever this is before winter comes.


----------



## ericgautier

chrismar said:


> I'm going to let it come out of regulation now, though. I'm seeing some fungusy looking blades and I'm hoping the aggressive urea apps + the cooler weather push out whatever it is. I know I'll be mowing every 3-4 days, but I want to kick out whatever this is before winter comes.


I'm actually doing the opposite. I had been throttling down the PGR last few weeks but will be throttling it up again for Fall till the end of the season.


----------



## chrismar

ericgautier said:


> I'm actually doing the opposite. I had been throttling down the PGR last few weeks but will be throttling it up again for Fall till the end of the season.


I've been going back and forth on this for a few days. I'll be traveling for 2 weeks at the end of Sept. If I were to get PGR down this week I'd have to re-apply while I was away. Rather than deal with the supposed explosive growth as regulation ends, I figured I'd just deal with that now and then I'd only have to deal with whatever the growth comes from the urea. I'll also miss urea apps those 2 weeks that I'm away, so I'm hoping the net-net is I won't have to chop too, too much off the top when I get back. Phew. Mouthful.


----------



## Ware

chrismar said:


> I've been going back and forth on this for a few days. I'll be traveling for 2 weeks at the end of Sept. If I were to get PGR down this week I'd have to re-apply while I was away. Rather than deal with the supposed explosive growth as regulation ends, I figured I'd just deal with that now and then I'd only have to deal with whatever the growth comes from the urea. I'll also miss urea apps those 2 weeks that I'm away, so I'm hoping the net-net is I won't have to chop too, too much off the top when I get back. Phew. Mouthful.


I wouldn't rule out a reduced rate PGR application now, then follow-up with a full rate application before you leave town. As I recall, biweekly applications at 1/2 the label rate are actually mentioned somewhere on the label.


----------



## chrismar

Ware said:


> I wouldn't rule out a reduced rate PGR application now, then follow-up with a full rate application before you leave town. As I recall, biweekly applications at 1/2 the label rate are actually mentioned somewhere on the label.


Hmmmm.... I hadn't considered that angle. Guess I need to put my thinking cap on again!


----------



## vnephologist

Was doing some tank mixing research and stumbled across this great article that discusses PGRs on Bentgrass, but has some other great bits for us cool season guys... http://gsr.lib.msu.edu/article/bigelow-plant-4-13-12.pdf. A couple of things that I found helpful...

"Another suggestion when using any of these PGRs is to tank-mix a small amount of soluble nitrogen, such as urea and/or a liquid chelated iron source. This will minimize discoloration and continue to stimulate growth/density without excess clipping production."

"By contrast, other species like Kentucky bluegrass may be discolored or injured by PGRs. This is important
because many golf courses have Kentucky bluegrass roughs or green/ tee surrounds, and paclobutrazol or mefluidide applications can cause subtle injury. These symptoms are less rare where flurprimidol or trinexapacethyl are used."

"One additional caution with PGR use: when using a DMI (demethylation inhibitor) fungicide in conjunction with a PGR program, understand that the combination of these materials may further regulate the turf."

"These results are encouraging and demonstrate that even with initial annual bluegrass populations of 30%, monthly root absorbed PGR applications throughout the growing season can effectively reduce populations to more tolerable (less than 10%) levels."


----------



## Pete1313

I wanted to cross-post this here from my renovation thread as there are a couple good links explaining PGRs and some of the benefits.



Pete1313 said:


> GrassFarmer said:
> 
> 
> 
> what is the primo and FAS stuff?
> 
> 
> 
> 
> 
> 
> J_nick said:
> 
> 
> 
> Primo is a plant growth regulator (PGR)
> 
> FAS is sprayable iron.
> 
> Click to expand...
> 
> 
> 
> 
> wardconnor said:
> 
> 
> 
> Im sure Pete will chime in but.... This is the stuff Dreams are made of.
> 
> Fas is liquid iron that gives the turf a dark green color. Awesome stuff
> 
> Primo is a plant growth regulator. It tricks (not sure this is the right term) the turf in to focusing on roots and lateral growth and kind of limits the top growth thus limiting the frequency of mowing. Even more awesome stuff.
> 
> Click to expand...
> 
> These guys did a good job explaining. It is some impressive stuff :thumbsup: Here is a list of some of Primo Maxx' s Benefits. In addition to those, there was some research from OSU saying that fall applications increased spring green up.
> All About PGRs
> "At OSU, the effects of spring green-up from fall TE applications on Kentucky bluegrass during August and September resulted in significantly faster spring green-up the following year, and the earlier green-up did not cause excessive top growth.
> 
> Sports turf managers with early spring sports like lacrosse and baseball may want to investigate using fall applications of TE in conjunction with a late-season fertilizer application to maximize green-up the following year."
Click to expand...

Also, I did see an earlier greenup last year on the old northern mix that I had to attribute to the fall Primo apps. There was a noticeable spray line between my property and the neighbors that would not be from the broadcasted fall urea apps alone. I believe Primo and fall fertilizer work really well together.

I also sprayed Primo+FAS on my bewitched renovation on day 56 and so far the results have been great. It is getting dense, darker, and put the brakes on the topgrowth. I have now gone 6 days between mowings at 7/8" and don't feel like I will be disobeying the 1/3rd rule when I cut today. As the days get shorter it is tough for me to get out and mow after work before it gets too dark.


----------



## HoosierLawnGnome

Always ask yourself first what you're considering using a PGR to accomplish. It can do a good bit to help accomplish some goals (seedhead reduction, reduced mowing, pre-summer stress conditioning, tighter knitted look / deeper color), but it can also be detrimental (exacerbated herbicide stress, disease pressure, less spreading) Know what you're doing and why.

In the spring, I focus on seedhead prevention with a combination of Proxy + Podium + FAS right at greenup, several applications in a row - then stop for the year. The Proxy can discolor some, although I haven't really noticed it on my new yard.

If your main objective is color on KBG, you absolutely CANNOT beat Podium (Primo Maxx) + FAS. Oh my - so nice, particularly in the fall.

For reduced mowing at lower heights, it is great. Not so helpful at reduced mowing if you're mowing at 3-4" in my experience.

For my situation, I'm currently avoiding fall PGR as I want the turf to grow like crazy and avoid the rust problems I've had (rust blown in from adjacent fields).

Once I start trying to lower HOC, my use of it will likely change. I do enjoy cutting, and can do ever 2-3 days no problem, but I can't cut every day.


----------



## j4c11

HoosierLawnGnome said:


> but it can also be detrimental (exacerbated herbicide stress, disease pressure, *less spreading*)


Can you tell us more about that? I was under the impression the reduced top growth would result in more energy being put towards tillering and rhizome production.


----------



## HoosierLawnGnome

j4c11 said:


> HoosierLawnGnome said:
> 
> 
> 
> but it can also be detrimental (exacerbated herbicide stress, disease pressure, *less spreading*)
> 
> 
> 
> Can you tell us more about that? I was under the impression the reduced top growth would result in more energy being put towards tillering and rhizome production.
Click to expand...

.

By less spreading, I mean less top growth in the short term which means less stuff to flop over into adjacent, empty spots.

IF you're applying Primo, the tillering it stimulates can help fill in longer-term of course.IF you're talking about Primo.. Not every PGR works the same way, of course.

So, for anyone reading this thread - make sure you understand the context of what someone means when they say "PGR".


----------



## SNOWBOB11

Hi all, so basically I'd like to join the spring 2018 pgr buy group but first had a couple pgr related questions that I was hoping to get some feedback on. Here goes.

1. I'm pretty sure I know the answer on this but just wanted to make sure. T-NEX pgr it is the exact same as primo maxx correct?

2. I just renovated my lawn to all kbg last fall and I want to make sure it's ok to use a pgr on a first year lawn. I saw Pete used it on his reno so I can't really think of a reason why it would be harmful to my lawn.

3. Basically I'm wanting to use pgr not so much to have to cut the lawn less as I enjoy cutting it, it's more because I'd like to increase density, tillering and colour and I've heard/seen than pgr in conjunction with FAS is a great way of doing this. This isn't really a question more just my reasoning on wanting to use it.

4. When do the cool season people start using pgr? After the spring growth flush? And about when do you stop? Before the nitrogen regime in the fall?

5. Would using pgr alter my fertilizers schedule any? I'm planning on using grains and urea in the spring to thicken the lawn up.

6. And finally is there anything I'm not thinking about that can be harmful to the lawn by using it? I think it would be of good benefit for my yard and can't really think of a reason not to give it a try but if anyone has something to add (pros or cons) don't hesitate to add your thoughts.


----------



## Sinclair

Interested.


----------



## chrismar

SNOWBOB11 said:


> 1. I'm pretty sure I know the answer on this but just wanted to make sure. T-NEX pgr it is the exact same as primo maxx correct?


I haven't checked in a few months, but I believe the AI is the same in both. So, yes, it's essentially the same.



> 2. I just renovated my lawn to all kbg last fall and I want to make sure it's ok to use a pgr on a first year lawn. I saw Pete used it on his reno so I can't really think of a reason why it would be harmful to my lawn.


Totally fine. If you have any lingering disease you may want to rethink your PGR strategy, but otherwise fine to use it on a newly renovated lawn.



> 3. Basically I'm wanting to use pgr not so much to have to cut the lawn less as I enjoy cutting it, it's more because I'd like to increase density, tillering and colour and I've heard/seen than pgr in conjunction with FAS is a great way of doing this. This isn't really a question more just my reasoning on wanting to use it.


It will definitely do this!



> 4. When do the cool season people start using pgr? After the spring growth flush? And about when do you stop? Before the nitrogen regime in the fall?


The consensus seems to be after 2 mows.



> 5. Would using pgr alter my fertilizers schedule any? I'm planning on using grains and urea in the spring to thicken the lawn up.


Nope. I didn't/don't alter my fert schedule when using PGR.



> 6. And finally is there anything I'm not thinking about that can be harmful to the lawn by using it? I think it would be of good benefit for my yard and can't really think of a reason not to give it a try but if anyone has something to add (pros or cons) don't hesitate to add your thoughts.


The only reason I can think of would be disease, as mentioned above. A lawn under PGR can take longer to kick out any disease due to it's slower growth.


----------



## SNOWBOB11

Thanks for the quick response chrismar. I did have some rust issues late last fall but I'm thinking since rust isn't as prevalent in the late spring as in fall the lawn should grow out of it. I'm going to give this a try this year and see how it goes.


----------



## Pete1313

+1 @chrismar

I'll add that when and if you back off of trinexapac-ethyl is a preference and depends on if you need to use the growth rebound to your advantage. 2 reasons for wanting the grass to rebound and grow faster would be to outgrow a disease/wear recovery or to help grow thru a leveling/topdressing project. I have used TE all the way thru fall for a couple seasons and the extra N combined with the TE play really nice together. There was research out of OSU that saw an earlier spring green up when using TE in August and September.

Trinexapac-ethyl generally provides better control on shorter turf compared to longer, so you will need to play around with application rates to find what works best for you. Lesser amounts will be needed for shorter turf, higher amounts for longer turf.

The amount of TE you apply affects the intensity of the suppression but not the duration. Higher TE rates will not get you longer control. There has been a lot of research showing duration of control is related to GDD. Most of the research has been done on bentgrass, but models are starting to come out for KBG. The current advice for KBG is to apply roughly every 280 GDD with a base 0°C which equals about every 500 GDD on base 32°F. By applying following GDD you could avoid TE over-regulation in spring/cooler weather and avoid any rebound in summer. Every 3 weeks was the general rule of how I applied it in years past. If you decide to apply using GDD, it could mean applying every 3-4 weeks in spring, but every 2 weeks in summer.


----------



## SNOWBOB11

@Pete1313 Thanks for the explanation. Especially the part about the amount you apply not having effects on the duration. I wouldn't have known that. Sorry but just one question, you lost me at GDD. I'm not sure what GDD means so I wasn't able to understand the last part of what you posted but would really like to know what you meant.


----------



## g-man

GDD = growing degree days

https://en.m.wikipedia.org/wiki/Growing_degree-day


----------



## Pete1313

Thanks g-man. In turf, GDDs can be used to help estimate other things too such as when to put down pre-m for crabgrass, when to expect weeds to show up, and when Japanese beetles will start emerging.
GDD Tracker

GDD Calculation


----------



## SNOWBOB11

Thanks guys. This cleared things up for me. I'm pumped now to use pgr this year. Too bad there's a foot of snow on the ground with another 8" expected this weekend. :lol:

Also thanks for posting the GDD tracker/calculator too. I need to look at these more.


----------



## g-man

What until Feb 15. That's when the tracker starts to work/calculate.


----------



## LawnNerd

I caught this snippet from that UNL paper posted.


Temperature scale: Most GDD models use degrees Fahrenheit (°F), but PGR models in turf use degrees Celsius (°C). Using °F or PGRs will result in too frequent of PGR applications. This wastes money and leads to over-regulation.

Base Temperature: It is essential to use the correct base temperature and associated temperature unit (°F vs °C). For PGR models, the base temperature is 0°C for cool-season turf but 10°C for warm season turf. The base temperature is 32°F for Poa annua seedhead control with Proxy while the seedhead flush model uses a base of 22°F.


I too am getting on the PGR train this year. With PGR if i can reduce the amount / frequency of mowing on my KBG then that's just one less stress on the plants. And for me, one less stress on the KBG could be the difference between good and blah...


----------



## Pete1313

Growing Degree Days and Trinexapac Applications

Cross posting this from the warm season forum in case it was missed.


----------



## 440mag

Greetings all (and TGIF)!

Quick question as I prepare to embark down the "PGR path" this season: are y'all adding any adjuvant or surfactant to your tanks when mixing in your Trinexapac-ethyl?

I've read the label on my Quali-Pro T-Nex very closely, oh, about a dozen times now and it only mentions "when using...use certified...." nothing about the efficacy or advisability of adding an adjuvant or surfactant.

I am going to go back and re-read some of the various university and PGR research papers I've archived but, I thought I'd inquire here, as well.

Thanks in advance for any ANSWERS to the question!


----------



## chrismar

@440mag did you read the thread? If not, you may wanna. It's chock full of tidbits, including whether a surfactant is recommended. 

Hint: It is!


----------



## 440mag

@chrismar from one well-intended snark to another :roll: thanks pal; and based on what I've ascertained since asking, if you have any way to reach them, YOU MIGHT WANT TO ENLIGHTEN researchers Tim R. Murphy, Ted Whitwell, L. B. McCarty and Fred Yelverton from The University of Georgia, Clemson University and North Carolina State University

In light of their findings: "It is not necessary to add a surfactant to trinexapac-ethyl."

http://caes2.caes.uga.edu/commodities/turfgrass/georgiaturf/WeedMngt/weedcontrol/PGR.htm

And yes, I've combed this thread numerous times; however; as you can imagine, I always try to reference more than one source of information.

"TRUST BUT, CONFIRM," and all that ... :thumbup:

Thanks again; and, Have a great (and safe!) weekend!


----------



## Ware

On the warm season side, some guys use NIS and some don't. I've done both and can't say I could tell a difference.


----------



## Pete1313

I use a surfactant with trinexapac-ethyl, but I also tank mix ferrous sulfate and ammonium sulfate.


----------



## 440mag

Thanks guys; just looking for straight answers;

a primary negative of ATY seemed to be an inability on the part of some of the more knowledgeable and experienced members to answer noob questions without tones which are either condescending or bordering on outright sniping. I hope that never takes root here but, guess I'll admit I may still hypersensitive to it ...


----------



## Sinclair

440mag said:


> Thanks guys; just looking for straight answers;
> 
> a primary negative of ATY seemed to be an inability on the part of some of the more knowledgeable and experienced members to answer noob questions without tones which are either condescending or bordering on outright sniping. I hope that never takes root here but, guess I'll admit I may still hypersensitive to it ...


It's a nasty environment. After lurking in both forums last spring I signed up here.


----------



## J_nick

Sinclair said:


> It's a nasty environment. After lurking in both forums last spring I signed up here.


We are happy to have ya!


----------



## kevreh

After reading this thread it doesn't sound like anyone is doing this for a tttf only lawn? Thats what I have and would like to give PGR a try, but not if its effectiveness on tttf is a lot less.


----------



## g-man

The label for T-nex does call out TTTF (0.75 rate), so it should work. From my experience, the level of control is affected not just by the grass type but also by the HOC. I would start at that 0.60 and go up in increments until you see the suppression you desire without discoloration. Leave a section untreated to use as your control plot.


----------



## Grassmasterwilson

I applied tnex to min a few weeks ago. It definitely slowed growth but we also went through a dry spell. I'm seeing a good amount of heat stress.

I'm in eastern NC and fescue is a true challenge. I could see using it more at the spring surge period with hopes of pushing roots.


----------



## kevreh

g-man said:


> The label for T-nex does call out TTTF (0.75 rate), so it should work. From my experience, the level of control is affected not just by the grass type but also by the HOC. I would start at that 0.60 and go up in increments until you see the suppression you desire without discoloration. Leave a section untreated to use as your control plot.


Thanks g-man. .75 seems like a good starting point.

Question about application. Do pgr's need to be applied with more of a spray or are "droplets" ok too. I bought a sprayer nozzle assembly from Pete at gci academy. Only thing is it's not an even spray but more of a spray of droplets, if that makes sense. I guess part of the equation is whether pgr's work as a foliar, soil, or both.


----------



## FuzzeWuzze

kevreh said:


> g-man said:
> 
> 
> 
> The label for T-nex does call out TTTF (0.75 rate), so it should work. From my experience, the level of control is affected not just by the grass type but also by the HOC. I would start at that 0.60 and go up in increments until you see the suppression you desire without discoloration. Leave a section untreated to use as your control plot.
> 
> 
> 
> Thanks g-man. .75 seems like a good starting point.
> 
> Question about application. Do pgr's need to be applied with more of a spray or are "droplets" ok too. I bought a sprayer nozzle assembly from Pete at gci academy. Only thing is it's not an even spray but more of a spray of droplets, if that makes sense. I guess part of the equation is whether pgr's work as a foliar, soil, or both.
Click to expand...

As i understand it, they are purely foliar. If its larger drops make sure your adding a good amount of surfactant.


----------



## kevreh

Thanks for the info Fuzze. I read an article linked on another thread and it also mentioned that they worked foliar only. The nozzle from GCI has a wider throw so you can cover your yard faster. In this case I'll use the tip (more narrow but a more even spray) that came with my sprayer.


----------



## crussell

I put down my first PGR last weekend - I went with the bottle rate of .7oz/K and I'm thinking it may have been a little heavy. I noticed very quick results, I went to mow two days after and had a hard time being able to even see where I was cutting! I think I'll back down to .5oz for the next app.

I had a couple areas that were filling in at my irrigation trenches - Looks to be young grass, and since my first app they have turned pale, and look dry and withered. Is this an effect from the PGR? It is not as brown as the photo makes it appear, more of a pale light green.


----------



## SNOWBOB11

@crussell I don't think that would be an effect from the PGR. FYI I applied my first app of PGR last week and I noticed much slower growth at just .35oz/k.


----------



## chrismar

crussell said:


>


Looks kinda diseased. Can you post closer pictures of the grass blades?


----------



## g-man

That looks like stressed lawn + too much pgr. The label warns against applying to a stressed lawn. I normally start low (0.4) and work up to a control.

How are you watering?


----------



## crussell

I water regularly (every other day) and we have had some recent rain this week. Watered 30 min / zone this morning.

I don't know if that grass was so much stressed, as it is just young and undeveloped? In either case should it recover?


----------



## g-man

How many inches of water you get in 30min in those zones? It looks like it is watered stressed and the PGR will make things harder for you since it cant grow out of it. You will need to baby the lawn for the next 3-4 weeks.

I looked at your weather. Last friday you had 0.29in of rain and nothing more. The weather looks nice for grow. I would ensure you are applying around 0.5in of water every 3 days (use a tuna can or similar). Once it shows some grow (it will be slow), feed it some nitrogen to push for grow.

Are you using the greenkeeperapp.com to track your t-nex applications and GDD? I would recomend not applying more t-nex until you get the grass healthy and growing again and use a lower rate (0.3-0.4). What is you hoc now?


----------



## crussell

I've never measured my irrigation - I know I need to, will do that this weekend. I do know that 30 min is a really good soak, visually speaking.

Just started using the greenskeeperapp this week, and haven't quite learned all of the features yet.

Current HOC is .70"


----------



## Pete1313

crussell said:


> I put down my first PGR last weekend - I went with the bottle rate of .7oz/K and I'm thinking it may have been a little heavy. I noticed very quick results, I went to mow two days after and had a hard time being able to even see where I was cutting! I think I'll back down to .5oz for the next app.
> 
> I had a couple areas that were filling in at my irrigation trenches - Looks to be young grass, and since my first app they have turned pale, and look dry and withered. Is this an effect from the PGR? It is not as brown as the photo makes it appear, more of a pale light green.


I'm assuming you applied trinexapac-ethyl? There are other PGRs. For a HOC of .70" I would stay closer to the fairway label rates of .25-.50 oz/M. Like mentioned already, can you take a closer pic of the blades but also take a zoomed out pic showing the whole area. Also did you mix anything else in (iron, N, NIS)? If so what was the rate/M. Calibrating/auditing your sprinkler system is important. Too little water can be bad, but too much water can be even worse.


----------



## Rule11

I am curious if any of you have used PGR (T-Nex) after seed and growth and when is it safe to apply PGR? I know the lable say it's recommended to apply 1-5 days before seeding. But not sure after germination and growth. I am at day 18 and have cut twice. So I am thinking I would like to start the T-Nex Applications.


----------



## pennstater2005

Giving this a bump. I don't know anything about PGRs myself.


----------



## pennstater2005

I also merged @@Rule11 PGR question here into the cool season PGR thread.


----------



## g-man

I never tried pgr on a new lawn. Maybe someone else could chime in.


----------



## kevreh

kevreh said:


> After reading this thread it doesn't sound like anyone is doing this for a tttf only lawn? Thats what I have and would like to give PGR a try, but not if its effectiveness on tttf is a lot less.


Going to quote myself to follow up. Applied .75oz before vacation. Up to that point I was cutting every 5 days. Was very pleased to come back after 12 days and my lawn didn't grow too much. I was actually able to wait a couple more days before cutting! So went from 5 day cutting interval to 14 day. We did get some hot weather, so I'm sure that slowed things too. But still I can say the PGR had a benneficial effect on my TTTF mix, which is typically cut @3.75".


----------



## bluenotgreen

I was going to wait till Sept to use PGR but my grass is still growing. I'm cutting twice a week. No irrigation . Should I start PGR now or just wait till the Fall? Temps are gonna be mid 80s next week.


----------



## g-man

I would start if it is not dormant/stressed. Go with a low rate at first (0.4oz/ksqft).

I restarted last Sunday.


----------



## bluenotgreen

@g-man Thanks for the detailed advice, I appreciate it. It's probably not going to go into dormancy soon. It made it through the heat wave and was still growing. Then yesterday we got 1.5" of water from an unexpected thunderstorm so I'm guessing it's gonna keep growing for now


----------



## Joehock57

Quick Q about PGR...apologies if this has been asked. Heat restriction? Doesn't look like it on label? Also noticed from label it recommends higher rates if turf is cut taller...anyone around 4 in have a recommended rate? Thanks!


----------



## chrismar

Joehock57 said:


> Quick Q about PGR...apologies if this has been asked. Heat restriction? Doesn't look like it on label? Also noticed from label it recommends higher rates if turf is cut taller...anyone around 4 in have a recommended rate? Thanks!


No heat restrictions on the PGR itself (if you're talking Primo or it's generics, t-pac, t-nex, etc). You should watch yourself if you're adding FAS or any other additives with temps over 85-90.

As far as dosage: Last season I was up to 1 oz per 1,000 SF on my KBG lawn at 4 inches. I got good control at that rate. This season I'm still at .75 oz / M and it's working just fine. Bottom line, YMMV, so start low and adjust as needed.


----------



## g-man

Be careful if lawn is dormant, per the label.


----------



## PROBOUND

Looking into ordering some PGR for my Canadian KBG. We are limited to ordering from SeedworldUSA.com for any types of pest/herbicides/PGR etc. T-NEX seems to be the most recommended brand of PGR in this thread but i can't find it anywhere on their site. Can anyone recommend a PGR product from this list that would be a good alternative?

https://www.seedworldusa.com/search?page=1&q=PGR


----------



## 01redcrew

i can start a new thread if i need to but i have a tttf with *** mixed in and i have to reseed some spots this fall. I farm for a living and just bought the t-nex to help not to make the wife mow much in the fall. When can i starting using this? Has anyone used it on new seed? Thanks


----------



## synergy0852

I saw a recommendation earlier in this thread for irrigation the morning after a PGR+FAS app during times of hot weather and I am curious if this is a general consensus or just personal preference.

Is it necessary/recommended to irrigate the following morning if the temps are going to be in the 80s or only if they will be 90°+?

What are the preferences of experienced PGR+FAS users?

Thanks


----------



## g-man

I like to wash off the Ammonium Sulfate (AS) from the leafs in the am. I've seen it cause some leaf burn.


----------



## synergy0852

Thanks g-man!


----------



## bluenotgreen

Man, this PGR stuff is a game changer. So grateful that I found TLF otherwise I wouldn't even know about it.
Especially thanks to @g-man and @Ware for opening my eyes to this awesome product.
Applied T-nex at .40oz/k per g-man's recommendation and getting great results even at my 4" cutting height


----------



## Ware

bluenotgreen said:


> Man, this PGR stuff is a game changer. So grateful that I found TLF otherwise I wouldn't even know about it.
> Especially thanks to g-man and Ware for opening my eyes to this awesome product.
> Applied T-nex at .40oz/k per g-man's recommendation and getting great results even at my 4" cutting height


Looks great! :thumbsup:


----------



## g-man

Just keep fine tuning your rate. Last week the grow potential was low due to the high temps most of us had. I went a week without mowing and could have waited even more based on clipping yields.

As the temps cool down, my forecast has me at 100% grow potential, that means I have to up the rate if I want the same level of control. There are some sections that could use some grow (polka dots from dollar spot), so I used the same rate (knowing that it will control less). This is my first time using the GDD model and I like the even control I'm getting.


----------



## 01redcrew

i can start a new thread if i need to but i have a tttf with *** mixed in and i have to reseed some spots this fall. I farm for a living and just bought the t-nex to help not to make the wife mow much in the fall. When can i starting using this? Has anyone used it on new seed? Thanks


----------



## SNOWBOB11

PROBOUND said:


> Looking into ordering some PGR for my Canadian KBG. We are limited to ordering from SeedworldUSA.com for any types of pest/herbicides/PGR etc. T-NEX seems to be the most recommended brand of PGR in this thread but i can't find it anywhere on their site. Can anyone recommend a PGR product from this list that would be a good alternative?
> 
> https://www.seedworldusa.com/search?page=1&q=PGR


If your willing to dish out the bucks you can get primo maxx which is the brand name version of T-nex. https://www.seedworldusa.com/search?q=Primo. Keep in mind I've read a bottle of PGR looses some of its effectiveness after around 3-4 years or so. Chances are you won't use even close to that size jug. Also keep in mind though that the stuff really does work.


----------



## chrismar

01redcrew said:


> i can start a new thread if i need to but i have a tttf with *** mixed in and i have to reseed some spots this fall. I farm for a living and just bought the t-nex to help not to make the wife mow much in the fall. When can i starting using this? Has anyone used it on new seed? Thanks


How long ago did you seed? The general consensus is you can use PGR after two mows.


----------



## 01redcrew

Haven't seeded yet going to around Labor Day. Just trying to get my ducks in a row


----------



## bluenotgreen

Thanks @g-man for the additional useful advice. I wasn't aware that this is such a fluid system seeing how you're varying your rate depending on weather conditions, etc.
When you say fine tune my rate, do you mean the concentration or the frequency, or both?

I am using the GDD model on the greenkeeper app although I need to read more about GDD to understand it better


----------



## Pete1313

chrismar said:


> 01redcrew said:
> 
> 
> 
> i can start a new thread if i need to but i have a tttf with *** mixed in and i have to reseed some spots this fall. I farm for a living and just bought the t-nex to help not to make the wife mow much in the fall. When can i starting using this? Has anyone used it on new seed? Thanks
> 
> 
> 
> How long ago did you seed? The general consensus is you can use PGR after two mows.
Click to expand...

You can use it now as long as you are not having any issues with the current grass that you are trying to grow thru(fungus) and it would be a good idea to time an app just before you seed as it will slow down the existing stand and give more opportunity for an overseed to grow. As far as when to use it on new seedlings, I tried it 55 days after seed down on my KBG reno with mixed results. By that I mean it regulated some plants but didn't seem to slow down the whole stand.

Waiting until after 2 mows is good advice on when to start using it when the lawn first wakes up in the spring.


----------



## 01redcrew

Thanks Pete. I'm just waiting to help the grass but still look good and not have the wife mow so much. Can I still use milo in the with pgr or will that outway one or the other


----------



## Pete1313

01redcrew said:


> Thanks Pete. I'm just waiting to help the grass but still look good and not have the wife mow so much. Can I still use milo in the with pgr or will that outway one or the other


No issues using milo or other N sources with it. I have had great results with primo and N even with an aggressive fall N plan. Reduced mowing is a main concern of yours, so watch the grass and if it is growing too much either cut back on the N alittle or play with the primo rates to get the control you are looking for.


----------



## g-man

@01redcrew I would apply it seed down day. I would try to avoid the new grass area (3 weeks). I would think you could apply it at 6 weeks. This is just what I think instead of what I know.


----------



## Pete1313

g-man said:


> @01redcrew I would apply it seed down day. I would try to avoid the new grass area (3 weeks). I would think you could apply it at 6 weeks. This is just what I think instead of what I know.


Sounds like good advice! :thumbsup:


----------



## g-man

@bluenotgreen the frequency doesn't change much and it is based on GDD. The concentration defines how much it suppresses. Too much and it causes yellowing. It will suppress based on how much it is growing. It grows based on temperature, water and fertilization (nitrogen).


----------



## PROBOUND

SNOWBOB11 said:


> PROBOUND said:
> 
> 
> 
> Looking into ordering some PGR for my Canadian KBG. We are limited to ordering from SeedworldUSA.com for any types of pest/herbicides/PGR etc. T-NEX seems to be the most recommended brand of PGR in this thread but i can't find it anywhere on their site. Can anyone recommend a PGR product from this list that would be a good alternative?
> 
> https://www.seedworldusa.com/search?page=1&q=PGR
> 
> 
> 
> If your willing to dish out the bucks you can get primo maxx which is the brand name version of T-nex. https://www.seedworldusa.com/search?q=Primo. Keep in mind I've read a bottle of PGR looses some of its effectiveness after around 3-4 years or so. Chances are you won't use even close to that size jug. Also keep in mind though that the stuff really does work.
Click to expand...

Thanks i'll check it out!


----------



## Creel

So from what I'm gathering is for when I go to overseed that it would probably be best to do an app a week or two before seed down?


----------



## g-man

@Creel Nope. Apply at seed down (same day or the day before). PGR takes a couple of days to take effect and it last ~3 weeks. If you want to mow less during the time the new seed is growing, then apply it so it last those 3 weeks.


----------



## Creel

g-man said:


> @Creel Nope. Apply at seed down (same day or the day before). PGR takes a couple of days to take effect and it last ~3 weeks. If you want to mow less during the time the new seed is growing, then apply it so it last those 3 weeks.


Thanks for the clarification. :beer: 
Was afraid maybe the PGR would affect the seed, but I'm still learning the PGR game but the grass definitely needs it hopefully get some better roots.


----------



## g-man

T-nex only works thru leaf absorption.


----------



## ryeguy

How significant is the greening effect on this? Is it noticeable enough to consider PGR if I'm ok with my rate of mowing?


----------



## bluenotgreen

PGR is working very well at .5oz/k. It's time for the next app in a couple days according to GDD.
It's rained about 12 out of the last 14 days here with high humidity and I've got some kind of what looks like fungus issue going on. Looks like it's only affecting the fine fescue. Does anyone know what this is? And should I continue with the PGR on schedule or should I let it try to grow itself out?


----------



## ryeguy

Thought this was interesting:










PGR had the best effect on resulting overseeding density when applied 5 days prior to seed down. The article also mentions you can apply again 4-6 weeks after seedling emergence.

from https://d2j31icv6dlhz6.cloudfront.net/O/aU41Q1r02O.pdf


----------



## TheSwede

ryeguy said:


> Thought this was interesting:
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> PGR had the best effect on resulting overseeding density when applied 5 days prior to seed down. The article also mentions you can apply again 4-6 weeks after seedling emergence.
> 
> from https://d2j31icv6dlhz6.cloudfront.net/O/aU41Q1r02O.pdf


Exactly what I was looking for! If my lawn wakes up anytime soon from the extreeme drought we've experienced this year I would like to do an overseed this fall and have tried to find information on using PGR prior to overseeding to give the overseeded grass a better chance to establish.

As it happens I also stumbled on an article from STERF (Scandinavian Turfgrass and Environment Research Foundation) that indicates that for Trinexapac-ethyl ,the GDD target needs to be adjusted if you're located far north (we're talking mid-Canada and north), since the longer days here up in the very north increases the production of gibberellic acid, and thereby increase cell elonogation:
http://www.sterf.org/Media/Get/1234/growth-regulation-with-primo-maxx-on-nordic-golf-courses


----------



## FuzzeWuzze

bluenotgreen said:


> PGR is working very well at .5oz/k. It's time for the next app in a couple days according to GDD.
> It's rained about 12 out of the last 14 days here with high humidity and I've got some kind of what looks like fungus issue going on. Looks like it's only affecting the fine fescue. Does anyone know what this is? And should I continue with the PGR on schedule or should I let it try to grow itself out?


Are you sure the fine fescue isnt just getting fried by heat? Its the first to go when under direct sunlight since its more a shade grass.


----------



## g-man

The sterf articles are very good and informative.


----------



## bluenotgreen

FuzzeWuzze said:


> bluenotgreen said:
> 
> 
> 
> PGR is working very well at .5oz/k. It's time for the next app in a couple days according to GDD.
> It's rained about 12 out of the last 14 days here with high humidity and I've got some kind of what looks like fungus issue going on. Looks like it's only affecting the fine fescue. Does anyone know what this is? And should I continue with the PGR on schedule or should I let it try to grow itself out?
> 
> 
> 
> 
> Are you sure the fine fescue isnt just getting fried by heat? Its the first to go when under direct sunlight since its more a shade grass.
Click to expand...

@FuzzeWuzze I think you're right. I don't know how the fine fescue got into and survived in the sunny areas in the first place. I think I read that@ken-n-nancy and @g-man are using tenacity to selectively kill off the fine fescue in their lawn. If it works for them, I have tenacity ready to go.

For now, I think I'm going to continue with the PGR like usual unless I hear otherwise from the pros on here


----------



## Mozart

ryeguy said:


> Thought this was interesting:
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> PGR had the best effect on resulting overseeding density when applied 5 days prior to seed down. The article also mentions you can apply again 4-6 weeks after seedling emergence.
> 
> from https://d2j31icv6dlhz6.cloudfront.net/O/aU41Q1r02O.pdf


This PGR stuff sounds like it will make overseeding a lot easier / better results. I'm new to PGR - what are some of the better options, brand wise? If it's not super expensive I might consider using it for overseeding.

Are there risks with applying a PGR (burn lawn, etc) if not done right?

How low would you generally cut before applying PGR to overseed?


----------



## GoPre

@Mozart it's great even in established turf. Helps tremendously with color and density.

For an overseed I would start to gradually lower your HOC now until the end of the month. Don't be afraid to scalp, the lawn will look rough for awhile. I think I was a little below 2 inches from 4, can make for an ugly lawn, for real.

Apply PGR a day or two before seed down. I have gone .75/k before and had a little yellowing on healthy turf, but since you'll be scalped it may be irrelevant to you.

I'd strongly consider the new starter fert with mesitrone as well, to combat the fall weed germination.


----------



## krusej23

I applied T-nex to the overseed reno area 2 days before kbg/prg seeding. Is it okay to apply T-nex to this area again in 4 weeks since there will be new grass growing?


----------



## ryeguy

krusej23 said:


> I applied T-nex to the overseed reno area 2 days before kbg/prg seeding. Is it okay to apply T-nex to this area again in 4 weeks since there will be new grass growing?


The article I linked a few posts up mentions you can apply again 4-6 weeks after seedling emergence.


----------



## Mozart

What impact does PGR have on 4-6 week old seedlings? Will the new turf grow more dense (more tillering) deeper roots, or would it stunt growth?


----------



## g-man

It should have the same impact as a full grown lawn. The gibberellic acid reduction reduces top grow. The extra energy has to go somewhere, so it goes to the roots or tillering.

I'm not sure what I think about pgr and a young kbg lawn. The article above seems to be for prg at athletic field hoc.


----------



## Joehock57

Hi all
Was wondering about fertilizing strategies with the use of T-nex during an overseed. Should I hold off on the N for a certain period of time so I don't negate the effects of the PGR? Maybe go with a stand alone Phos fertilizer at or around seed down? Or am I overthinking this completely...hah. First time PGR user. Apologies if this has been asked before, thank you in advance for your input. Have a great day all.


----------



## chrismar

Joehock57 said:


> Hi all
> Was wondering about fertilizing strategies with the use of T-nex during an overseed. Should I hold off on the N for a certain period of time so I don't negate the effects of the PGR? Maybe go with a stand alone Phos fertilizer at or around seed down? Or am I overthinking this completely...hah. First time PGR user. Apologies if this has been asked before, thank you in advance for your input. Have a great day all.


The beauty of PGR is the extra N shouldn't push top growth, but instead redirect that energy into root development and tillering. I wouldn't (and don't) hold off on N while using PGR.


----------



## Joehock57

No kidding! That is truly a thing of beauty :thumbup: . Thanks for your response.


----------



## g-man

@Joehock57 you can reduce the amount of nitrogen while using pgr. This report from a Soldat and Kreuser study has more info

https://turf.unl.edu/pdfctarticles/Grass%20Roots%20PGR%20N.pdf


----------



## Mozart

What is the optimal interval for applying PGR? Once every 4 weeks?

Is it safe to use T-Nex in a vegetable garden (and does it help produce fruit)?


----------



## chrismar

Every 3 weeks for the lawn.

I wouldn't use it on veggies.


----------



## Mozart

chrismar said:


> Every 3 weeks for the lawn.
> 
> I wouldn't use it on veggies.


Ok thanks - when do you start/stop using it in spring/fall? Is this something that you stop using once you achieve results, or do you use it to maintain as well? Trying to figure out how much I would need to buy.


----------



## chrismar

Start after 2 mows in the spring. I continue throughout the season. Will probably stop after one more app to get me through the end of sept.


----------



## g-man

@chrismar using gdd is way better than the 3 weeks. I ended up doing it every 2 weeks based on gdd.

T-nex can be used on some veggies and shrubs but not all. Check the label. There are other pgr for vegetables and shrubs.


----------



## chrismar

@g-man yah, I know. The green keeper app is blocked in my office and I didn't have the energy to sit down and figure it out while at home yet. Maybe next season.


----------



## bluenotgreen

What is the time window of applying PGR before rain?
Also how much time after being cut until I can apply PGR?


----------



## zeus201

bluenotgreen said:


> What is the time window of applying PGR before rain?
> Also how much time after being cut until I can apply PGR?


I don't have the label in front of me but I thought you had to wait an hour after mowing. I do and don't though and will apply after mowing or wait a bit. Honestly depends on how much time I have. No ill effects from doing right after mowing.

I apply with iron so I like to let it sit for several hours before irrigation or rainfall. I imagine majority of it is absorbed within the first hour.

Hopefully brighter minds will chime in.


----------



## JP900++

Probably a silly question. I'm planning on hitting my current lawn with T-Nex before aerating and then overseeding. Want to stall it out and give the seed a head start on the growth. Any advice and or opinions?

TTTF (4th Millennium, Cochise, & Bullseye) with some KBG( Blue Velvet, Bewitched) and Bandera HBG in the existing lawn BTW.


----------



## chrismar

JP900++ said:


> Probably a silly question. I'm planning on hitting my current lawn with T-Nex before aerating and then overseeding. Want to stall it out and give the seed a head start on the growth. Any advice and or opinions?
> 
> TTTF (4th Millennium, Cochise, & Bullseye) with some KBG( Blue Velvet, Bewitched) and Bandera HBG in the existing lawn BTW.


Totally an acceptable use of PGR. Should work well for you!


----------



## g-man

What is the question?


----------



## JP900++

Any random tips...things to avoid?


----------



## g-man

One of the problems with pgr is rebound. Ideally you are already in regulation. The question you need to answer is, apply more pgr (your new seeds and the existing lawn, or let it go out of regulation and grow like crazy (thus the need to mow))


----------



## JP900++

Thanks. I'm diving in tomorrow night. Cut to about 1.5 inches tonight. Going to aerate and seed on Saturday. Hopefully the PGR won't knock it back too far, given how late it is.


----------



## zeus201

JP900++ said:


> Thanks. I'm diving in tomorrow night. Cut to about 1.5 inches tonight. Going to aerate and seed on Saturday. Hopefully the PGR won't knock it back too far, given how late it is.


Skip seeding and save it for next year. You are honestly past ideal seed down date to give seed chance to germinate and grow a decent root structure to survive winter or even the first frost.


----------



## GoPre

PGR is wonderful, but I've put it away for the year once I started my blitz.

When I returned from vacation in early August my lawn had some fungal issues appearing, and was starting to look a little ragged. I wanted to push some growth, and thankfully my blitz was right around the corner.

I've also been reading around that people are uncertain about using PGR with heavy nitrogen apps, so I'm not regretting putting it away for now...

Anyone have any knowledge or opinion on PGR use with an aggressive blitz?


----------



## JP900++

zeus201 said:


> JP900++ said:
> 
> 
> 
> Thanks. I'm diving in tomorrow night. Cut to about 1.5 inches tonight. Going to aerate and seed on Saturday. Hopefully the PGR won't knock it back too far, given how late it is.
> 
> 
> 
> Skip seeding and save it for next year. You are honestly past ideal seed down date to give seed chance to germinate and grow a decent root structure to survive winter or even the first frost.
Click to expand...

Probably true...but I subscribe to the philosophy " Nothing in life is ever ideal"...plus I'm in it now. Aeration done...seed done...5 days for the 4th Millennium to germinate. Fingers crossed.


----------



## ryeguy

When people talk about rebound, does that refer to when the PGR wears off and the grass starts growing normally again, or is there actually a period of accelerated growth once it wears off? If it's accelerated, how long does that last until it grows normally again?


----------



## g-man

Rebound is an above normal grow. It last around the same time the suppression last.

This thread has some info. The link has the full cycle of t-nex graph.

https://thelawnforum.com/viewtopic.php?t=1670&start=40


----------



## 440mag

j4c11 said:


> I use T-Nex 1AQ. Split a jug with another gentleman last year, a whole gallon would probably last me 5-6 years and there's a shelf life.


Shelf Life appears to be "*The shelf life of T-Nex is 3-5 years from the date of purchase if stored in a dry place away from extreme temperatures."*

...this year, from mid-Dec til mid-March, I'll be moving what's left in my PGR jug, along with all my chems inside to a storage area I'm setting up in the basement, from the garage (even tho it's insulated it stays very cold out there!)


----------



## NJ-lawn

How about using primo with the aggressive urea treatments? Urea pushes top growth and Primo max seems to do the opposite. How do they effect each other?


----------



## Green

g-man said:


> One of the problems with pgr is rebound. Ideally you are already in regulation. The question you need to answer is, apply more pgr (your new seeds and the existing lawn, or let it go out of regulation and grow like crazy (thus the need to mow))


I have a method for reducing or eliminating the rebound effect when stopping. It works.


----------



## Miggity

Green said:


> I have a method for reducing or eliminating the rebound effect when stopping. It works.


You can't just drop a bread crumb like that.  I just read a 10 page thread on PGR when I have never seen or used it before and it ends in a cliffhanger.


----------



## Green

Miggity said:


> Green said:
> 
> 
> 
> I have a method for reducing or eliminating the rebound effect when stopping. It works.
> 
> 
> 
> You can't just drop a bread crumb like that.  I just read a 10 page thread on PGR when I have never seen or used it before and it ends in a cliffhanger.
Click to expand...

Lol!

Ok, what I do is when it's due for the last app, I let it begin to rebound for like a day or two...just on the verge. And then I spray a really low rate, like 0.1oz per M. It's just enough to slow the rebound down. I will likely use the Greenkeeper app to try to time it right.


----------



## Pete1313

Green said:


> Ok, what I do is when it's due for the last app, I let it begin to rebound for like a day or two...just on the verge. And then I spray a really low rate, like 0.1oz per M. It's just enough to slow the rebound down. I will likely use the Greenkeeper app to try to time it right.


Interesting strategy @Green! My last Primo app was on 9/8 at .125oz/M and although the Greenkeeper app says I should be in a 20% rebound, I am not seeing an excessive growth surge. I applied my last app right as the GDD model called for it to be reapplied. The reduced rate of .125oz/M seems to be minimizing the rebound. I like what you are suggesting in delaying the final app until it just starts to rebound(as well as the reduced rate) and will try it that way next time.


----------



## Green

@Pete1313, my guess is that it works because of the half-life principle. Maybe someone who likes math can plot the growth as a function of reapplication so we can visually understand it better.


----------



## MMoore

Planning a google calendar for next year... what else do you do in the winter LOL

When do you guys start your PGR in the spring? How about we use a relative timing with spring pre-e because of different climates.


----------



## zeus201

MMoore said:


> Planning a google calendar for next year... what else do you do in the winter LOL
> 
> When do you guys start your PGR in the spring? How about we use a relative timing with spring pre-e because of different climates.


After your second mow you can start PGR. I waited till May, after several mows, to start and didnt stop till mid September. Some people go longer, I just wanted the grass to come out of regulation.


----------



## chrismar

Some things just aren't that cut and dry. Just like you can't put the pre-m on the calendar. It depends on soil temps and other environmental factors.

For pgr, the general school of thought is after two mows. I don't know about you, but I can't plan out my first mow in November of the previous year.


----------



## MMoore

that's understandable.

I am referencing the soil temp website (greencastonline) and setting alerts.

We are having a kid in roughly march which I hope to get these things on a warning so I don't miss my window in that initial fog of sleeplessness.


----------



## zeus201

Quoting j4c11 here but this what i did. Applied every two weeks at about the same rate. Created a reoccurring notification and applied on the same day barring any weather issues. This kept it easy / simple for me even though Greenskeeper app is a great tool.

Perhaps create the calendar, start applying after your second mow and enjoy the benefits.



j4c11 said:


> Now that I've been using it for 2 years, PGR is one of the things I wouldn't do lawn care without. I apply 0.35oz/K trinexapac every 2 weeks, and the benefits I've noticed are:
> - Slows down growth and reduces the amount of mowing needed. When I do mow, there's far less clippings.
> - Increases density,
> - Significantly enhances color.
> - Reduces seed heads
> - Increases root mass
> - Does wonders for me as far as drought resistance through the summer.
> 
> It's a jug of magic


----------



## Green

chrismar said:


> For pgr, the general school of thought is after two mows. I don't know about you, but I can't plan out my first mow in November of the previous year.


Exactly. One year my first mow was in May, and another year, the last day of February!


----------



## FORT

Hello!

I did a full reno of my lawn this past September and I am working on my 2019 Lawn Plan and reading about PGRs it sounds like adding a PGR to my lawn plan can help my new grass handle stress and disease pressures better. So my question is when would I want to start applying a PGR (when growing season starts, right before summer heat hits)? Any guidance is appreciated.


----------



## chrismar

FORT said:


> Hello!
> 
> I did a full reno of my lawn this past September and I am working on my 2019 Lawn Plan and reading about PGRs it sounds like adding a PGR to my lawn plan can help my new grass handle stress and disease pressures better. So my question is when would I want to start applying a PGR (when growing season starts, right before summer heat hits)? Any guidance is appreciated.


I've updated the first post of this thread to have a small FAQ section that answers this, and other common questions.

Cool season PGR experts, please feel free to let me know other FAQs that should be added to the first post. Thanks!


----------



## FORT

chrismar said:


> FORT said:
> 
> 
> 
> Hello!
> 
> I did a full reno of my lawn this past September and I am working on my 2019 Lawn Plan and reading about PGRs it sounds like adding a PGR to my lawn plan can help my new grass handle stress and disease pressures better. So my question is when would I want to start applying a PGR (when growing season starts, right before summer heat hits)? Any guidance is appreciated.
> 
> 
> 
> I've updated the first post of this thread to have a small FAQ section that answers this, and other common questions.
> 
> Cool season PGR experts, please feel free to let me know other FAQs that should be added to the first post. Thanks!
Click to expand...

Thanks! :thumbup:


----------



## g-man

Thanks for doing this. I think adding the start low (0.3) and go higher as the season starts. Also, a section of risks: doesn't grow out of fungus as fast.


----------



## chrismar

@g-man, done!


----------



## 440mag

g-man said:


> Thanks for doing this. I think adding the start low (0.3) and go higher as the season starts. Also, a section of risks: doesn't grow out of fungus as fast.


My heart skipped a beat when I read this (which I didn't know) as fighting fungus in my clime is a CONSTANT battle with some growing seasons worse than others.

Then I realized I combined my fungicide app. with my PGR app.s onto the same day - made things infinitely simpler last year and worked fantastic so, I'll repeat in 2019.

(Done massaging my left chest now :lol: )


----------



## stotea

chrismar said:


> *Q: Are there any risks associated with applying a PGR?*
> A: You betcha! For starters, if you apply too much your yard will look FUGLY until it wears off, and you might experience some die-off. Additionally, if your lawn has some sort of disease/fungus the PGR can prevent the disease from growing out as quickly as it would if it weren't under regulation.


If my Bewitched gets rust and PWM to some degree every year, should I avoid PGR?


----------



## chrismar

Those diseases are pretty weak in the gamut or lawn disease.

I don't know what the official answer is, but I do know that different parts of my lawn get those diseases at different times of the season, and I applied plenty of PGR, and the condition of those diseases wasn't any worse (or better) in years that I hadn't applied PGR.

How's that for a run on sentence!!?


----------



## Scagfreedom48z+

chrismar said:


> Those diseases are pretty weak in the gamut or lawn disease.
> 
> I don't know what the official answer is, but I do know that different parts of my lawn get those diseases at different times of the season, and I applied plenty of PGR, and the condition of those diseases wasn't any worse (or better) in years that I hadn't applied PGR.
> 
> How's that for a run on sentence!!?


If you apply PGR in conjunction with Azoxy/Prop(preventive dose) at the same, you could avoid the fungal outbreak and get the benefits of the PGR, correct?

Is there any contraindications of applying an anti fungal and PGR at the same time?

It makes sense to me that I would apply both at the same time, but I may be totally wrong.


----------



## chrismar

I do apply PGR with Serenade, if anything as more as a preventative.

I did have an outbreak of something that required two curative applications of Azoxy to wipe out. I applied that while under PGR, though, and everything was just fine.


----------



## Scagfreedom48z+

chrismar said:


> I do apply PGR with Serenade, if anything as more as a preventative.
> 
> I did have an outbreak of something that required two curative applications of Azoxy to wipe out. I applied that while under PGR, though, and everything was just fine.


Awesome. I'm glad to hear that the experience didn't have any adverse effects. I'm planning on combining them both when applying next year to cut down on time


----------



## Ware

Kreuser's work sheds light on PGR use
Posted By John Reitman (TurfNet)


----------



## g-man

^ +1. I want to get to measuring my clippings yields. I haven't figured out a way of doing it at a residential level without too much effort.


----------



## Suburban Jungle Life

Could you mark out a 200x200 section and bag it when mowing? Random size pulled from thin air... Do it like this? Mow every day? yikes! Maybe every 3 days or something. I'm sure leaf retained moisture will have a large effect on this. Perhaps also note the length of blade in addition to weight to compare 2 numbers?


----------



## rfi_

Hello everyone.

Looking at using Trinexapac-Ethyl this year to improve turf density more than anything (color and mowing reduction are certainly nice too though). I've got a largely weed-free KBG/PRG/Fescue mix lawn that's much more thin than I would like.

I'm planning to start apps after my second mow at 1/2 rates every two weeks.

How much density does Trinexepac-Ethyl provide? I've always seen it as a side effect, but I find it hard to gauge how much better the turf is in videos and pix.

Would I be better off just running generous rates of good slow release fertilizer and reel mowing and irrigating super often this season?

I already overseed, just looking to do the most possible.

Thanks.


----------



## g-man

Welcome to TLF.

I start at 0.2oz/ksqft and go up to 0.3-0.4oz/ksqft during the season at 1in hoc. I follow the gdd model. I don't have a good way to compare with vs without it as a function of density.


----------



## HoosierLawnGnome

rfi_ said:


> Hello everyone.
> 
> Looking at using Trinexapac-Ethyl this year to improve turf density more than anything (color and mowing reduction are certainly nice too though). I've got a largely weed-free KBG/PRG/Fescue mix lawn that's much more thin than I would like.
> 
> I'm planning to start apps after my second mow at 1/2 rates every two weeks.
> 
> How much density does Trinexepac-Ethyl provide? I've always seen it as a side effect, but I find it hard to gauge how much better the turf is in videos and pix.
> 
> Would I be better off just running generous rates of good slow release fertilizer and reel mowing and irrigating super often this season?
> 
> I already overseed, just looking to do the most possible.
> 
> Thanks.


Applying PGR for cosmetics is something to do after you've made the most of a good fertilization, weed control, and cultivation practice. Get those right first, you'll get the most from those basics. Watering more frequently can be detrimental, so read up on deep and infrequent.....


----------



## rfi_

HoosierLawnGnome said:


> rfi_ said:
> 
> 
> 
> Hello everyone.
> 
> Looking at using Trinexapac-Ethyl this year to improve turf density more than anything (color and mowing reduction are certainly nice too though). I've got a largely weed-free KBG/PRG/Fescue mix lawn that's much more thin than I would like.
> 
> I'm planning to start apps after my second mow at 1/2 rates every two weeks.
> 
> How much density does Trinexepac-Ethyl provide? I've always seen it as a side effect, but I find it hard to gauge how much better the turf is in videos and pix.
> 
> Would I be better off just running generous rates of good slow release fertilizer and reel mowing and irrigating super often this season?
> 
> I already overseed, just looking to do the most possible.
> 
> Thanks.
> 
> 
> 
> Applying PGR for cosmetics is something to do after you've made the most of a good fertilization, weed control, and cultivation practice. Get those right first, you'll get the most from those basics. Watering more frequently can be detrimental, so read up on deep and infrequent.....
Click to expand...

Thanks guys. Even though I *REALLY* wanted to break out the Trinexapac-Ethyl, I'm going to hold off and see how far good cultural practices can help things this year.


----------



## zeus201

rfi_ said:


> HoosierLawnGnome said:
> 
> 
> 
> 
> 
> rfi_ said:
> 
> 
> 
> Hello everyone.
> 
> Looking at using Trinexapac-Ethyl this year to improve turf density more than anything (color and mowing reduction are certainly nice too though). I've got a largely weed-free KBG/PRG/Fescue mix lawn that's much more thin than I would like.
> 
> I'm planning to start apps after my second mow at 1/2 rates every two weeks.
> 
> How much density does Trinexepac-Ethyl provide? I've always seen it as a side effect, but I find it hard to gauge how much better the turf is in videos and pix.
> 
> Would I be better off just running generous rates of good slow release fertilizer and reel mowing and irrigating super often this season?
> 
> I already overseed, just looking to do the most possible.
> 
> Thanks.
> 
> 
> 
> Applying PGR for cosmetics is something to do after you've made the most of a good fertilization, weed control, and cultivation practice. Get those right first, you'll get the most from those basics. Watering more frequently can be detrimental, so read up on deep and infrequent.....
> 
> Click to expand...
> 
> Thanks guys. Even though I *REALLY* wanted to break out the Trinexapac-Ethyl, I'm going to hold off and see how far good cultural practices can help things this year.
Click to expand...

You can still use cultural practices while using it. Just another tool to help. I honestly thought my turf was WAY better using it combination with good practices than all the previous years.

I sprayed it with fungicides and FAS with no harmful affects. Like Nike says, "Just Do It". You will not regret it.


----------



## ryeguy

Does PGR affect watering requirements in any way? Does growth regulated grass use more or less water?


----------



## craigdt

zeus201 said:


> You can still use cultural practices while using it. Just another tool to help. I honestly thought my turf was WAY better using it combination with good practices than all the previous years.
> 
> I sprayed it with fungicides and FAS with no harmful affects. Like Nike says, "Just Do It". You will not regret it.


Nice to hear about mixing. Maybe I need to make a separate topic, but I wonder if I can mix PGR, FEature, and Propiconazole? Sounds like they'd all do fine


----------



## Drewmey

I am hopping on this thread because I don't think this question warrants a new post.

What are some of the benefits of using PGR on a TTTF lawn other than mowing less? I get the advantages with grasses that spread but fescue obviously doesn't. So are we seeing increased root growth with use? My grass seems to have a nice dark green color with FAS, so I am not anticipating markedly different results with color. I sometimes struggle with fungus...would a spring PGR routine increase root depth and lead to a higher tolerance for fighting fungus or grubs (if caught late)?


----------



## ryeguy

Drewmey said:


> I am hopping on this thread because I don't think this question warrants a new post.
> 
> What are some of the benefits of using PGR on a TTTF lawn other than mowing less? I get the advantages with grasses that spread but fescue obviously doesn't. So are we seeing increased root growth with use? My grass seems to have a nice dark green color with FAS, so I am not anticipating markedly different results with color. I sometimes struggle with fungus...would a spring PGR routine increase root depth and lead to a higher tolerance for fighting fungus or grubs (if caught late)?


I was reading these slides and came across this list of advantages to PGRs:

• Increased color, quality and density
• Increased water use efficiency
- Slightly lower ET (King et al., 1997: Marcum and Jiang, 1998; Ervin and Koski, 2001)
- Increase salinity tolerance and improved dry down (Jiang and Fry, 1998; Pessarakli et al., 2006)
• Improved heat stress tolerance
- More stress hormones and antioxidants (Ervin and Zhang, 2003)
- Increase sod storage life in heat (Heckman et al., 2001 & 2002)
• Increased non-structural carbohydrates
- During suppression phase (Han et al., 1998 & 2004; Richie 2001; and Ervin and Zhang, 2007)


----------



## Drewmey

ryeguy said:


> I was reading these slides and came across this list of advantages to PGRs:
> 
> • Increased color, quality and density
> • Increased water use efficiency
> - Slightly lower ET (King et al., 1997: Marcum and Jiang, 1998; Ervin and Koski, 2001)
> - Increase salinity tolerance and improved dry down (Jiang and Fry, 1998; Pessarakli et al., 2006)
> • Improved heat stress tolerance
> - More stress hormones and antioxidants (Ervin and Zhang, 2003)
> - Increase sod storage life in heat (Heckman et al., 2001 & 2002)
> • Increased non-structural carbohydrates
> - During suppression phase (Han et al., 1998 & 2004; Richie 2001; and Ervin and Zhang, 2007)


Thanks increased density and heat tolerance is always appreciated. Would salinity tolerance help with help with dog urine spots?


----------



## Pete1313

craigdt said:


> Nice to hear about mixing. Maybe I need to make a separate topic, but I wonder if I can mix PGR, FEature, and Propiconazole? Sounds like they'd all do fine


I had some issues tank mixing trinexapac-ethyl and propiconazole last year. The grass turned alittle unsightly, thinned alittle, and seemed to be over-regulated. DMI fungicides have some growth regulating effects and wonder if that caused the over regulation. Also I read about cautioning DMI use in hot weather.

First time:
T-Nex = .3 oz/M
Propiconazole = 1 oz/M

Second time:
T-Nex = .125 oz/M
Propiconazole = 1 oz/M

Both times they were tank mixed together and were not washed down afterwards in the evening. I wonder if washing in the Propiconazole would have helped. Anyone else have issues or success tank mixing the two together?


----------



## craigdt

Pete1313 said:


> craigdt said:
> 
> 
> 
> Nice to hear about mixing. Maybe I need to make a separate topic, but I wonder if I can mix PGR, FEature, and Propiconazole? Sounds like they'd all do fine
> 
> 
> 
> I had some issues tank mixing trinexapac-ethyl and propiconazole last year. The grass turned alittle unsightly, thinned alittle, and seemed to be over-regulated. DMI fungicides have some growth regulating effects and wonder if that caused the over regulation. Also I read about cautioning DMI use in hot weather.
> 
> First time:
> T-Nex = .3 oz/M
> Propiconazole = 1 oz/M
> 
> Second time:
> T-Nex = .125 oz/M
> Propiconazole = 1 oz/M
> 
> Both times they were tank mixed together and were not washed down afterwards in the evening. I wonder if washing in the Propiconazole would have helped. Anyone else have issues or success tank mixing the two together?
Click to expand...

Thanks for the input on this. I'm trying to reduce the number of times I have to drag my sprayer around with my 900 pound mower :lol:


----------



## chrismar

I haven't tank mixed T-PAC + Propiconazole, but I have tank mixed T-PAC + Serenade without any issue at all.


----------



## mribbens

I just got off the phone with my local rep from Quali Pro, what a great guy. He also only lives 5 minutes from me, and he offered to come over to help with my first ever application of PGR, it is great news. He spent 18 years as a GC super in the Chicago area, a wealth of knowledge. So he gave me some very useful tips on how to apply, rates and how much water to use when mixing T-Nex. He told me to put down the low rate to start, .4 oz/M, just like @@Pete1313 told me, and that should be mixed with 1 gallon of water for every 1000 sq ft. I have to calibrate my pump sprayer first to make sure I am putting down 1 gallon every 1K, which can be done on my driveway. This is serious rabbit hole stuff, but hopefully the first app will go smooth. If any of you are in the Chicagoland area and want his info, PM me, glad to share!!


----------



## gm560

I think this weekend will be my first FEature + T-Nex app, so this morning I was revisiting the T-Nex label and this thread. It looks like the label says best practice is to mow right before application or a few hours after?



> Turfgrass injury can be minimized by using one of the following options:
> 1. Mow 4 hours after the application of Quali-Pro® T-Nex®;
> OR
> 2. Mow 1 hour before application of Quali-Pro® T-Nex®.


Is this what you guys do? Does the foliar iron change anything? I think I am going to mix in some Serenade, too, as we have been getting a bunch of rain and I want to get some preventative fungicide down.


----------



## chrismar

I'll mow first or spray the next day. Most often it's different days all together as it's just too much for one day.

If you're applying FAS or just iron (I guess that's what FEature is?), be sure to irrigate the morning after. Spray iron should be washed off the blade after a few hours or you risk a blackish, gnarly looking lawn for a few days.


----------



## gm560

Cool, thanks Chris. Maybe I'll get the mow in today and save the spray for tomorrow. That way mother nature can wash it off for me with the rain forecasted on Sunday and Monday.


----------



## g-man

I mow and spray right after. Once I have yard clothing on, I try to do it all. What rate are you thinking?


----------



## gm560

Going to follow the advice I have read on this thread... start low and work my way up. Going to start at 0.35 oz/K and see where I am in 2 weeks. Or should I go even lighter to start?


----------



## g-man

What's your hoc?


----------



## gm560

g-man said:


> What's your hoc?


2 inches via rotary, at present.


----------



## g-man

To me 0.35 sounds good to start at that hoc.


----------



## TrialAndError

I have a TTTF lawn with a 3" HOC currently. I'm going to use PGR for the first time, mainly to promote tillering. I'd like to tank mix .5 oz / 1000 of T-NEX with 3oz / 1000 of both N-EXT MicroGreene and GreeneEffect. I'd also add .5oz / 1000 of GCI Natural Adjuvant. Anybody see any issues with this?


----------



## Jayray

Piggy backing on this thread also, I have 1 inch KBG and I'm currently needing to mow every 3-4 days. I'm going to apply T-NEX for the first time and I am thinking of going for the full rate (.75) as I am going to be gone for 2 weeks and won't be able to mow. I am hoping I can get back and not have to scalp too much and then catch it on rebound at the perfect time to go thick (1/2 inch) with sand for leveling. What are the risks of over application? I don't have anyone I can trust to use my reel mower to mow when I am gone.


----------



## g-man

@TrialAndError I dont if all those products are compatible to be mixed in a tank. Test it out. Also make sure they are all foliar applications since the PGR needs to be foliar.


----------



## g-man

@Jayray I keep my yard at 1in and I use 10mL/M (0.33oz/M). I tried going higher but the kbg had issues with the high rate (turned yellow). The grow regulation takes like 3-5 days to go into real effect. In your case, I would do 0.5oz/M 4 days before your trip and mow the night before the trip. Timing all of this with rain could be a challenge. Use the greenkeeperapp to track your GDD and reapply when it tells you.


----------



## ryeguy

g-man said:


> @Jayray I keep my yard at 1in and I use 10mL/M (0.33oz/M). I tried going higher but the kbg had issues with the high rate (turned yellow). The grow regulation takes like 3-5 days to go into real effect. In your case, I would do 0.5oz/M 4 days before your trip and mow the night before the trip. Timing all of this with rain could be a challenge. Use the greenkeeperapp to track your GDD and reapply when it tells you.


Does the rate affect the GDD calculation (higher=longer duration)? Or just the strength of suppression? I would imagine both but wanted to see what your experience was.


----------



## osuturfman

Rate will not affect the GDD calculations. The research showed that temperature was the only determining factor in how quickly the degradation of the active ingredient passed the point of effectiveness. Find a rate that provides adequate suppression and then stick to the GDD intervals.


----------



## g-man

I used Bill Kreuser data to develop this chart. I checked it the greenkeeperapp last year. I need to check if they changed the values.

For greens hoc, the gdd threshold is constant, for others it all follows this chart. It might be from the lack of research (higher hoc).



In tabular format:
From the GreenKeeper Website 
T-Nex rate	GDD 0C Threshold	
0.125	261	
0.25	280	
0.3	287	
0.35	294	
0.4	300	
0.5	317	
0.55	323	
0.6	330	
0.75	353	
0.8	360	
1	389


----------



## ryeguy

Thanks, that's super helpful. Looks like for every 0.1 oz/m applied it bumps the GDD interval 14c/57f which is about an extra day or two.


----------



## osuturfman

ryeguy said:


> Thanks, that's super helpful. Looks like for every 0.1 oz/m applied it bumps the GDD interval 14c/57f which is about an extra day or two.


Lack of research as this is extrapolated from greens data. There's a PhD candidate at Penn State who will be doing this type of work with TE on high cut (lawn height) turf beginning this spring/summer. Hopefully, we have better info in the near future.


----------



## MassHole

This thread was super informative. Thanks to everyone for all the info.

I have some questions:
- any pics of the before / after results?
- if i started using PGR now, and put down Milo or other N, do they counteract? Or does the N go to color and root growth?
- how much root mass growth was observed?
- how profound is the color impact?


----------



## MassHole

What rate do others use when mowing high? Say 3" or 4"?

I hit my first spot at 4" with 0.4 oz/K, and then another with 0.5 oz/K. I'm thinking that since it's foliar, I will need to use more, as the T-Nex label lists 0.75 oz/K for edging (which I assume is taller grass).

Looking forward to seeing the deltas.


----------



## FORT

I have put down 2 apps at .38 oz/K 14 days apart with good success. My HOC is 3.5 inches. I plan on staying at this rate/HOC till fall.


----------



## MassHole

FORT said:


> I have put down 2 apps at .38 oz/K 14 days apart with good success. My HOC is 3.5 inches. I plan on staying at this rate/HOC till fall.


Excellent. So in 6 week period, that's .114 oz/K vs my 0.1 oz/K.

Thank you. Any comparison pics?


----------



## MassHole

MassHole said:


> FORT said:
> 
> 
> 
> I have put down 2 apps at .38 oz/K 14 days apart with good success. My HOC is 3.5 inches. I plan on staying at this rate/HOC till fall.
> 
> 
> 
> Excellent. So in 6 week period, that's .114 oz/K vs my 0.1 oz/K.
> 
> Thank you. Any comparison pics?
Click to expand...

Nevermind. Reread your thread. Love the color! Good luck on the house sale!


----------



## FORT

@MassHole Thanks, we close on June 17th!


----------



## g-man

@FORT so a new lawn to renovate this fall?

@MassHole I think Eric or chrismar used 1oz/M last year on their high hoc applications. The frequency doesn't change too much.


----------



## chrismar

That's correct. I get good regulation at 1 oz/M on a 4" HOC.


----------



## FORT

@g-man New build, they put down sod 3 weeks ago. I have a friend that lives near by and I have him drive by to make sure they are watering it lol. No irrigation system so that will probably be the first thing I do.


----------



## MassHole

chrismar said:


> That's correct. I get good regulation at 1 oz/M on a 4" HOC.


Can you give me your feedback? How often? Did you use NIS? Did you stop in the fall? Thoughts on thickness vs color?


----------



## MassHole

@mribbens some info you bro.


----------



## chrismar

MassHole said:


> chrismar said:
> 
> 
> 
> That's correct. I get good regulation at 1 oz/M on a 4" HOC.
> 
> 
> 
> Can you give me your feedback? How often? Did you use NIS? Did you stop in the fall? Thoughts on thickness vs color?
Click to expand...

Last year I applied every 3 weeks starting after my 2nd mow for the season. I did so until labor day weekend, when I started the fall blitz. In retrospect I should have continued through the fall blitz, and that's what I'll probably do this year.

I did use NIS, a tablespoon per gallon. Thickness and color were excellent for the duration. Color is clearly enhanced when applying with FAS.


----------



## MassHole

chrismar said:


> Last year I applied every 3 weeks starting after my 2nd mow for the season. I did so until labor day weekend, when I started the fall blitz. In retrospect I should have continued through the fall blitz, and that's what I'll probably do this year.
> 
> I did use NIS, a tablespoon per gallon. Thickness and color were excellent for the duration. Color is clearly enhanced when applying with FAS.


Excellent. I am anxious to see my results having done my first app last week. Thanks for your input. Have you considered mowing higher?


----------



## chrismar

Higher than 4"? No, definitely not. I'm at 3.75" right now, and will probably stay at that length for the entire season. Longer (even at 4") it starts to look unruly a day or two after a mow.


----------



## GMM

2 weeks into using PGR + FAS for the first time and I'm loving the results. I half dosed FAS at that, so I'm really excited to see what a full dose looks like.


----------



## mribbens

@chrismar I am planning my 2nd app of T-Nex this Friday, about 3 weeks since my 1st, I would like to include Ferromec AC-Liquid Iron in my sprayer, all good to mix the 2? I ask because I experienced a touch of yellowing in parts of the lawn with .4 oz/M first app, this would help that yellowing? I am planning on using the same rate, .4 oz/M, HOC is between 2.25-2.5.


----------



## Scagfreedom48z+

I'm trying to mow off and bagging as many seed stocks from all the POA T that has popped up this spring. Would it be better for me to wait to apply TNex after the seed heads are done? I just don't want more seed to spread


----------



## MassHole

mribbens said:


> @chrismar I am planning my 2nd app of T-Nex this Friday, about 3 weeks since my 1st, I would like to include Ferromec AC-Liquid Iron in my sprayer, all good to mix the 2? I ask because I experienced a touch of yellowing in parts of the lawn with .4 oz/M first app, this would help that yellowing? I am planning on using the same rate, .4 oz/M, HOC is between 2.25-2.5.


That's what I did. 4 oz / K.


----------



## mribbens

MassHole said:


> mribbens said:
> 
> 
> 
> @chrismar I am planning my 2nd app of T-Nex this Friday, about 3 weeks since my 1st, I would like to include Ferromec AC-Liquid Iron in my sprayer, all good to mix the 2? I ask because I experienced a touch of yellowing in parts of the lawn with .4 oz/M first app, this would help that yellowing? I am planning on using the same rate, .4 oz/M, HOC is between 2.25-2.5.
> 
> 
> 
> That's what I did. 4 oz / K.
Click to expand...

Did you have any yellowing of the grass? Did you apply with Liquid Iron?


----------



## MassHole

mribbens said:


> MassHole said:
> 
> 
> 
> 
> 
> mribbens said:
> 
> 
> 
> @chrismar I am planning my 2nd app of T-Nex this Friday, about 3 weeks since my 1st, I would like to include Ferromec AC-Liquid Iron in my sprayer, all good to mix the 2? I ask because I experienced a touch of yellowing in parts of the lawn with .4 oz/M first app, this would help that yellowing? I am planning on using the same rate, .4 oz/M, HOC is between 2.25-2.5.
> 
> 
> 
> That's what I did. 4 oz / K.
> 
> Click to expand...
> 
> Did you have any yellowing of the grass? Did you apply with Liquid Iron?
Click to expand...

No yellowing. 4 oz /K of FerromacAC with 0.4 oz / K in one gallon of water.


----------



## mribbens

Right on, thank you @MassHole


----------



## Scagfreedom48z+

I'm trying to mow off and bagging as many seed stocks from all the POA T that has popped up this spring. Would it be better for me to wait to apply TNex after the seed heads are done? I just don't want more seed to spread


----------



## MassHole

Scagfreedom48z+ said:


> I'm trying to mow off and bagging as many seed stocks from all the POA T that has popped up this spring. Would it be better for me to wait to apply TNex after the seed heads are done? I just don't want more seed to spread


I thought poa triv doesn't seed until 12 inch heights per Jonathan Green customer service. Are you sure it's not just KBG going to seed, which are likely sterile anyways?

I want to try and get more roots and tillering in the cool months before the summer heat here in Mass, so I started PGR last week (and already seeing a difference after 10 days). I wouldn't wait.


----------



## Scagfreedom48z+

MassHole said:


> Scagfreedom48z+ said:
> 
> 
> 
> I'm trying to mow off and bagging as many seed stocks from all the POA T that has popped up this spring. Would it be better for me to wait to apply TNex after the seed heads are done? I just don't want more seed to spread
> 
> 
> 
> I thought poa triv doesn't seed until 12 inch heights per Jonathan Green customer service. Are you sure it's not just KBG going to seed, which are likely sterile anyways?
> 
> I want to try and get more roots and tillering in the cool months before the summer heat here in Mass, so I started PGR last week (and already seeing a difference after 10 days). I wouldn't wait.
Click to expand...

I apologize, I meant POA A


----------



## Jayray

I sprayed T-nex at .5/K and got no noticeable suppression. It didn't even appear to give me an extra day. Can I spray again on day 10? And can I spray in the rain? I might just go for the full label rate @ .75. (1 inch KBG)


----------



## g-man

Leave a test area without suppression in the future to see the difference. At 0.5oz /ksqft at 1in hoc should see suppression. I do 10mL/ksqft (0.33oz) at 1in hoc and it is suppress. Get to 14days before doing another application. Don't spray in the rain. It should have 4hrs before rain/irrigation.


----------



## MassHole

I noticed a big color delta between 5 day and 10 day areas, and in the strips of increased height where I didn't overlap when spraying. I'm a fan so far...


----------



## Scagfreedom48z+

MassHole said:


> I noticed a big color delta between 5 day and 10 day areas, and in the strips of increased height where I didn't overlap when spraying. I'm a fan so far...


Just curious, any pictures of your before and after results?


----------



## MassHole

Scagfreedom48z+ said:


> MassHole said:
> 
> 
> 
> I noticed a big color delta between 5 day and 10 day areas, and in the strips of increased height where I didn't overlap when spraying. I'm a fan so far...
> 
> 
> 
> Just curious, any pictures of your before and after results?
Click to expand...

Before and after is hard b/c color is so dependent on lighting, angles, sun. I prefer to compare it to other sections of the lawn in the same picture to eliminate those factors.

Bottom was 0.4 oz/K PGR + 4 oz AC/K Ferromac AC ten days ago
Top at 0.5 oz/K PGR + 6 oz AC/K Ferromac AC five days

You can see the taller grass along the bottom edge of the driveway is taller where I didn't hit.


----------



## Scagfreedom48z+

There's definitely a color change there for sure! I'm trying to find a good time to apply feature and pgr. The weather up here has been absolute crap


----------



## MassHole

Scagfreedom48z+ said:


> There's definitely a color change there for sure! I'm trying to find a good time to apply feature and pgr. The weather up here has been absolute crap


It sucks. I put down Milo on Saturday and hoping that the warmer temps + PGR + FerromacAC turn up the color on the main front lawn.


----------



## Scagfreedom48z+

Did you water in your ferromac and pgr?

I'm definitely itching to get the PGR and FEature down ASAP but I'm battling small bouts of red thread right now and I'm a little apprehensive on putting it down until it clears


----------



## GMM

So after 2 weeks, I'm realizing I definitely screwed up. Maintaining pure KBG at 1.5" and applied T-Nex at 0.6oz/k. I've got a lot of yellowing, potentially dead grass, and stunted growth (haven't cut since I applied).

Once it comes back, going to try a test patch in the backyard at 0.3oz/k


----------



## g-man

@GMM give it fast nitrogen (AS) and water it.


----------



## Pete1313

GMM said:


> So after 2 weeks, I'm realizing I definitely screwed up. Maintaining pure KBG at 1.5" and applied T-Nex at 0.6oz/k. I've got a lot of yellowing, potentially dead grass, and stunted growth (haven't cut since I applied).
> 
> Once it comes back, going to try a test patch in the backyard at 0.3oz/k


What else if anything did you mix with it? Have you applied anything else? 5 days ago you reported good results. How has the weather been the past week.

All that said, I have noticed the grass get a little funky looking in previous years using trinexapac-ethyl, especially the first app of the season. I think it's a good idea to go low for the first app of the year, half rate of what you intend to be at and work your way up during the next apps.

If it is just from the trinexapac-ethyl, and could be an overregulation, it will bounce back.


----------



## GMM

Pete1313 said:


> GMM said:
> 
> 
> 
> So after 2 weeks, I'm realizing I definitely screwed up. Maintaining pure KBG at 1.5" and applied T-Nex at 0.6oz/k. I've got a lot of yellowing, potentially dead grass, and stunted growth (haven't cut since I applied).
> 
> Once it comes back, going to try a test patch in the backyard at 0.3oz/k
> 
> 
> 
> What else if anything did you mix with it? Have you applied anything else? 5 days ago you reported good results. How has the weather been the past week.
> 
> All that said, I have noticed the grass get a little funky looking in previous years using trinexapac-ethyl, especially the first app of the season. I think it's a good idea to go low for the first app of the year, half rate of what you intend to be at and work your way up during the next apps.
> 
> If it is just from the trinexapac-ethyl, and could be an overregulation, it will bounce back.
Click to expand...

I applied FAS the day after. I also had what I thought was a case of yellow patch in a few spots, but now realize it was actually overregulation.


----------



## Pete1313

GMM said:


> I applied FAS the day after. I also had what I thought was a case of yellow patch in a few spots, but now realize it was actually overregulation.


Did you put down any fungicide?


----------



## GMM

Pete1313 said:


> GMM said:
> 
> 
> 
> I applied FAS the day after. I also had what I thought was a case of yellow patch in a few spots, but now realize it was actually overregulation.
> 
> 
> 
> Did you put down any fungicide?
Click to expand...

I put down propiconazole at 3oz/k once the yellowing became apparent, 11 days after PGR treatment.


----------



## Pete1313

GMM said:


> I put down propiconazole at 3oz/k once the yellowing became apparent, 11 days after PGR treatment.


If it was overregulation, the propiconazole might have made the situation worse. I mentioned mixing them together a few posts back and how I saw some thinning and overregulation, but applying them separate could have a similar issue. https://thelawnforum.com/viewtopic.php?f=9&t=533&start=220#p143849


----------



## Jayray

The label rate is .6 to .75 and it even says you can go double that if desired (with temporary discoloration). Why would a normal rate application on that tall of grass do that?

Has anyone gotten any KBG suppression with TNex? My seed heads are the worse they have ever been and this is my first year using PGR.


----------



## g-man

@Jayray which tall grass?

Tnex suppresses top growth but not seedheads. A different pgr (proxy) will suppress seedheads if applied at the correct time.


----------



## mribbens

MassHole said:


> Scagfreedom48z+ said:
> 
> 
> 
> 
> 
> MassHole said:
> 
> 
> 
> I noticed a big color delta between 5 day and 10 day areas, and in the strips of increased height where I didn't overlap when spraying. I'm a fan so far...
> 
> 
> 
> Just curious, any pictures of your before and after results?
> 
> Click to expand...
> 
> Before and after is hard b/c color is so dependent on lighting, angles, sun. I prefer to compare it to other sections of the lawn in the same picture to eliminate those factors.
> 
> Bottom was 0.4 oz/K PGR + 4 oz AC/K Ferromac AC ten days ago
> Top at 0.5 oz/K PGR + 6 oz AC/K Ferromac AC five days
> 
> You can see the taller grass along the bottom edge of the driveway is taller where I didn't hit.
Click to expand...

Looks great, your color and thickness look amazing!!

I applied T-Nex this past Friday at .4oz/M with 4 oz/M of Ferromec for my cocktail, def seeing an improvement in color and thickness as well.


----------



## Thick n Dense

Guys, so I read through the first 8 pages of this thread and have a few questions.

What product/active ingridient should I buy to reduce topgrowth and increase tillering and spreading of kentucky bluegrass?
.
Is T-nexx the best for this?

My understanding is that they all work sligthly differently. I just want to be told what to buy lol

Also, does anyone change their fert strategy when using PGR's?
Think about it, top-growth ceases, so does all that extra N get wasted or does the plant use this for root growth?

Seems like either way overall N will be reduced.

I've been spoon feeding Urea weekly at .25#'s to encourage spreading.


----------



## Pete1313

Trinexapac-ethyl is what you want. T-nex I believe is still the best priced. Top growth is reduced, so the result should be more energy directed to the roots. I dont change my fert strategy. I know @g-man posted a while back about some research about less nitrogen being removed in a study, however it was when removing clippings in a putting green. Not sure how that applies when mulch mowing. I'm sure he will chime in in a bit.


----------



## g-man

With t-nex, you can reduce your nitrogen by ~20% and have a similar turf quality than no pgr.

Also to be clear, pgr will reduce top growth, but it will not cease/stop.


----------



## MassHole

Put down the second app of T-Nex last night.

*Front side lawn on 4" GCI TTTF & Midnight KBG:*
I put down 0.4 oz/K on May 7th with 4 oz/K of FerromacAC
I put down 0.45 oz/K on May 20th (+13 days)​
*Front main lawn on 4" GCI TTTF & Midnight KBG:*
I put down 6 oz/K of FerromacAC May 7th
I put down 0.5 oz/K on May 11th
I put down 0.45 oz/K on May 20th (+9 days) with 0.55 oz/K of Azoxystrobin fungicide (starting to get red thread)​
I had some slow down of growth, but not complete stopping. The side with the reduced FerromacAC but earlier T-Nex is definitely darker.


----------



## MassHole

mribbens said:


> Looks great, your color and thickness look amazing!!
> 
> I applied T-Nex this past Friday at .4oz/M with 4 oz/M of Ferromec for my cocktail, def seeing an improvement in color and thickness as well.


Thanks. Your color is great. How high are you mowing?


----------



## g-man

MassHole said:


> I had some slow down of growth, but not complete stopping. The side with the reduced FerromacAC but earlier T-Nex is definitely darker.


FYI, PGR will reduce top growth, but it will not stop it.


----------



## mribbens

MassHole said:


> mribbens said:
> 
> 
> 
> Looks great, your color and thickness look amazing!!
> 
> I applied T-Nex this past Friday at .4oz/M with 4 oz/M of Ferromec for my cocktail, def seeing an improvement in color and thickness as well.
> 
> 
> 
> 
> 
> 
> 
> Thanks. Your color is great. How high are you mowing?
Click to expand...

Thank you, this portion of the yard was cut at 2.75, at some point soon, maybe Thursday, I will get it down to 2.5. It is so thick and dense right now. One of the uses of PGR for me is to allow me to cut the yard at 2.25-2.5 all year, as it looks great, wears great with the kids playing on it and feels nice on the feet. The Ferromec really popped the color this time, may apply it at 4 oz/M with every T-Nex app.


----------



## MassHole

mribbens said:


> Thank you, this portion of the yard was cut at 2.75, at some point soon, maybe Thursday, I will get it down to 2.5. It is so thick and dense right now. One of the uses of PGR for me is to allow me to cut the yard at 2.25-2.5 all year, as it looks great, wears great with the kids playing on it and feels nice on the feet. The Ferromec really popped the color this time, may apply it at 4 oz/M with every T-Nex app.


Looks great! The kids like it longer for playing plus my lawn isn't level, but shorter can look very good, and I'm half tempted to cut shorter and lawn level this fall with sand.


----------



## MMoore

will PGR hurt or benefit an area of my lawn that needs to fill in? KBG specific.


----------



## Thick n Dense

Well just pull the trigger on T-nexx...

My apps will be Chelated iron, humic acid, t-nexx, serenade, surfactant and a dash of urea(like the equivilent of .1#/k)

Anyone see a problem with the cocktail above ?


----------



## GoPre

Thick n Dense said:


> Well just pull the trigger on T-nexx...
> 
> My apps will be Chelated iron, humic acid, t-nexx, serenade, surfactant and a dash of urea(like the equivilent of .1#/k)
> 
> Anyone see a problem with the cocktail above ?


I'll let the pros chime in, but I don't think Serenade will like being mixed with all of that. Its a live culture.


----------



## ryeguy

Thick n Dense said:


> Well just pull the trigger on T-nexx...
> 
> My apps will be Chelated iron, humic acid, t-nexx, serenade, surfactant and a dash of urea(like the equivilent of .1#/k)
> 
> Anyone see a problem with the cocktail above ?


I would vote for putting at least humic acid in its own app since it is a soil app (meaning you'd use more waterroduct than you would for the other products).


----------



## chrismar

I've tank mixed PGR + FAS + Serenade multiple times, no issues.


----------



## Thick n Dense

ryeguy said:


> Thick n Dense said:
> 
> 
> 
> Well just pull the trigger on T-nexx...
> 
> My apps will be Chelated iron, humic acid, t-nexx, serenade, surfactant and a dash of urea(like the equivilent of .1#/k)
> 
> Anyone see a problem with the cocktail above ?
> 
> 
> 
> I would vote for putting at least humic acid in its own app since it is a soil app (meaning you'd use more waterroduct than you would for the other products).
Click to expand...

So my theory on the humic is that since I'm blanket spraying its just another oppurtunity to get it down. I guess itll just hang around until water washes it in.

Or could it interfere with absorbtion?


----------



## ryeguy

Thick n Dense said:


> ryeguy said:
> 
> 
> 
> 
> 
> Thick n Dense said:
> 
> 
> 
> Well just pull the trigger on T-nexx...
> 
> My apps will be Chelated iron, humic acid, t-nexx, serenade, surfactant and a dash of urea(like the equivilent of .1#/k)
> 
> Anyone see a problem with the cocktail above ?
> 
> 
> 
> I would vote for putting at least humic acid in its own app since it is a soil app (meaning you'd use more waterroduct than you would for the other products).
> 
> Click to expand...
> 
> So my theory on the humic is that since I'm blanket spraying its just another oppurtunity to get it down. I guess itll just hang around until water washes it in.
> 
> Or could it interfere with absorbtion?
Click to expand...

That's a good question, I have no idea. The question is does it lose anything hanging around on the leaf blade and re-drying? Can the sun/UV rays degrade it? Or does it just sit there and rehydrate once mulch mowed and watered in?

I wish I knew, because I'd love to just tank mix it with other foliar sprays.


----------



## MassHole

chrismar said:


> I've tank mixed PGR + FAS + Serenade multiple times, no issues.


Sorry - what's Serenade?


----------



## ericgautier

MassHole said:


> Sorry - what's Serenade?


Serenade is a type of Biofungicide. :thumbup:


----------



## g-man

@MassHole here is more info around this bacteria Bacillus subtilis.

Serenade


----------



## Thick n Dense

ryeguy said:


> Thick n Dense said:
> 
> 
> 
> 
> 
> ryeguy said:
> 
> 
> 
> I would vote for putting at least humic acid in its own app since it is a soil app (meaning you'd use more waterroduct than you would for the other products).
> 
> 
> 
> So my theory on the humic is that since I'm blanket spraying its just another oppurtunity to get it down. I guess itll just hang around until water washes it in.
> 
> Or could it interfere with absorbtion?
> 
> Click to expand...
> 
> That's a good question, I have no idea. The question is does it lose anything hanging around on the leaf blade and re-drying? Can the sun/UV rays degrade it? Or does it just sit there and rehydrate once mulch mowed and watered in?
> 
> I wish I knew, because I'd love to just tank mix it with other foliar sprays.
Click to expand...

This would be great to know!

I always assumed that somthing like SLS would hang out until washed in via rain.... what if the plant absorbs it ? 
Will the clippings later decompose and release the SLS into the soil? Or is so chemically different that its not even SLS anymore?


----------



## MassHole

g-man said:


> @MassHole here is more info around this bacteria Bacillus subtilis.
> 
> Serenade


Love this group. Thanks! :thumbup:


----------



## MassHole

20 days post PGR first app and 7 after second. Can you see the dividing line?


----------



## Thick n Dense

Sprayed for first time today at .6 oz. however my walking speed was a tad fast so probably got closer to the .4-.5 oz range.

Did some iron and N, excited to see the results. Left some grass untouched for comparison.

Wife keeps telling me I need to cut lower... perfect excuse to play with PGR!


----------



## Thick n Dense

So I have a questions about rhizomes and PGR's and was hoping someone knows.

When does the plant switch from considering a rhizome to a leaf?
Meaning when does the vertical growth of a rhizome that just popped up out of the soil slow down dueto the regulator kicking in ?

Or does it because the growth regulator wasnt sprayed on this new leaf?

Not sure it really matters but fascinates me.


----------



## Miggity

@Thick n Dense Since you mention rhizomes in a cool season thread, I'm going to assume you are referring to KBG. At least T-Nex is systemic, but not through the rhizomes to the daughter plants, so they need to be hit with an application as well. I doubt newly emerging (untreated) daughter plants would grow noticeably above the treated parent plant's height (possible exception for reel mowing heights) before re-application was necessary for continued control. See this link for more detail.


----------



## Stuofsci02

I put down PGR at 0.5 oz per thousand mixed with a light app of AG chelated iron at 4oz per thousand. This was on Monday. Yesterday I noticed all the tips on the grass were yellow, as if my blades are not sharp.. they are sharp.

Is this a side effect of the PGR? This is the first time I have used it..


----------



## g-man

Pictures? First application of the year? Hoc?


----------



## MassHole

Noticing major growth restriction after the second app of T-Nex in my PGR. I have some fungus, but it looks like the Azoxy I mixed in is controlling it. I'd like to move again to get rid of the ugly seed heads. 4" HOC.

Planning to spray N-Ext RGS and Humic 12, and powdered molasses this weekend to help increase microbial activity to ward off thatch.


----------



## lobitz68

Stuofsci02 said:


> I put down PGR at 0.5 oz per thousand mixed with a light app of AG chelated iron at 4oz per thousand. This was on Monday. Yesterday I noticed all the tips on the grass were yellow, as if my blades are not sharp.. they are sharp.
> 
> Is this a side effect of the PGR? This is the first time I have used it..


From what I understand, it could be. How tall do you mow your grass? If it is super short that might be too much to put down at once. I recently did my yard for the first time with iron at around .3 oz/m and it is dark blue green. No signs of stress. I am mowing short in preparation for my reel mower arriving soon, but I am still above 1" for sure... probably 1.5-1.75".


----------



## Stuofsci02

g-man said:


> Pictures? First application of the year? Hoc?


Hi G-Man... HOC is 2.5". This is the first application of the year... In fact my first ever. I can take some pics when I get home from work..


----------



## g-man

It could be phototoxicity, but I doubt it at that high hoc. Let see pictures this afternoon.


----------



## Stuofsci02

Here is the pic... I double cut at 2.5" two days ago, and the second cut I was going really fast, so it may just be that I did not get a clean cut. I cut tonight at 2.5" and took the tips off and it looks great again.. hopefully will still look good two days from now..


----------



## Thick n Dense

Guys, can someone link the ammonium sulfate product they use?

Im too anal to choose one on my own.

Thanks


----------



## g-man

https://www.advancedturf.com/product/21-0-0-ammonium-sulfate/

https://www.ruralking.com/dsm-ammonium-sulfate-51lb-bag

Or any other 21-0-0.


----------



## Scagfreedom48z+

Stuofsci02 said:


> I put down PGR at 0.5 oz per thousand mixed with a light app of AG chelated iron at 4oz per thousand. This was on Monday. Yesterday I noticed all the tips on the grass were yellow, as if my blades are not sharp.. they are sharp.
> 
> Is this a side effect of the PGR? This is the first time I have used it..


I too have the same issue. 
Put down .5 oz of TNEX per 1M and 2 oz of FEature per 1M

I have seen some yellowing for sure in the lawn. Does the grass grow out of this or survive this type of stress?


----------



## Stuofsci02

Scagfreedom48z+ said:


> Stuofsci02 said:
> 
> 
> 
> I put down PGR at 0.5 oz per thousand mixed with a light app of AG chelated iron at 4oz per thousand. This was on Monday. Yesterday I noticed all the tips on the grass were yellow, as if my blades are not sharp.. they are sharp.
> 
> Is this a side effect of the PGR? This is the first time I have used it..
> 
> 
> 
> I too have the same issue.
> Put down .5 oz of TNEX per 1M and 2 oz of FEature per 1M
> 
> I have seen some yellowing for sure in the lawn. Does the grass grow out of this or survive this type of stress?
Click to expand...

. Well just my tips were yellow as seen in the pics. When I cut tonight I removed the tips so it looks good again...


----------



## lobitz68

Scagfreedom48z+ said:


> Stuofsci02 said:
> 
> 
> 
> I put down PGR at 0.5 oz per thousand mixed with a light app of AG chelated iron at 4oz per thousand. This was on Monday. Yesterday I noticed all the tips on the grass were yellow, as if my blades are not sharp.. they are sharp.
> 
> Is this a side effect of the PGR? This is the first time I have used it..
> 
> 
> 
> I too have the same issue.
> Put down .5 oz of TNEX per 1M and 2 oz of FEature per 1M
> 
> I have seen some yellowing for sure in the lawn. Does the grass grow out of this or survive this type of stress?
Click to expand...

It will grow out of it... you may want to reduce the amount of PGR you are using and/or slightly increase the iron. That should ensure it doesn't happen again. Once you get it dialed in you should be good to go.


----------



## ryeguy

Stuofsci02 said:


> Here is the pic... I double cut at 2.5" two days ago, and the second cut I was going really fast, so it may just be that I did not get a clean cut. I cut tonight at 2.5" and took the tips off and it looks great again.. hopefully will still look good two days from now..


It looks like those tips are torn which isn't the PGR. It may have been due to an unclean cut as you suspected.


----------



## Stuofsci02

Thanks RyeGuy!


----------



## ales_gantar

First time spraying PGR at 12,5ml(25%)/100sqm, it looks greyish (must switch blades and sharpen this one). That's it. I did not leave an untreated spot, because I just forgot.


----------



## NJ-lawn

g-man said:


> https://www.advancedturf.com/product/21-0-0-ammonium-sulfate/
> 
> https://www.ruralking.com/dsm-ammonium-sulfate-51lb-bag
> 
> Or any other 21-0-0.


Can someone explain why they use a liquid fert to other products?


----------



## g-man

I don't understand the question. @NJ-lawn


----------



## NJ-lawn

I was wondering why it helps other products work better. Like it says here,

Try adding DSM Ammonium Sulfate to your mixtureas an Adjuvant / Supplement in your water soluble agricultural sprays, such as fungicides, herbicides and insecticides. With a special binding function to iron and calcium in the plants cell structure, repeat treatments are few and far between saving you money in fewer applications. It is predominantly operative with Amine 2, 4-D, glufosinate herbicides and glyphosate.

Is that why most here us it?


----------



## g-man

Ammonium sulfate helps the leaves absorb more product.


----------



## Thick n Dense

PgRs are awesome! Amazed by this product!
Adds a dark green plus density to the grass.
This was cut at 2 and 3/4 last night... ive never been able to get it below 3" without scalping. 
I may try for 2 1/4" tommorow. 
I mixed enough for the front for my first app and went but had some leftover so i went around the fence line with it. Definitly 100% magic.

I agree with posters that Ill never do lawn care without this. 
I wonder if fert companies put this out with their mixes. Makes sense for a better looking lawn but literally takes business away from the cutting business...

When does the rebound kick in if applied at .4 oz rate? 
2 weeks or 3?


----------



## g-man

The duration of suppression and then rebound are a function of temperature. In this thread or the other one (warm and cool season one) I did the math once. Rebound peak is around double the reapplication gdd threshold.

Follow the greenkeeperapp application time and you will be fine.


----------



## Thick n Dense

g-man said:


> The duration of suppression and then rebound are a function of temperature. In this thread or the other one (warm and cool season one) I did the math once. Rebound peak is around double the reapplication gdd threshold.
> 
> Follow the greenkeeperapp application time and you will be fine.


Thanks @g-man 
Forgot about that app!
Also, i can see getting a reel mower in the next couple of years... but need to smooth and adjust sprinker heads... thats my next big challenge. Fixing the jacked up sprinkler system. Mismiatched heads, not having head to head coverage and just straight no coverage spots. Front is pretty solid, the back needs work though.

Also may do some frenchs's.
Well say within 2 years...


----------



## Stuofsci02

My neighbor and I went in on 2.5 gal of PGR (we have an acre of turf between us)... We are both really impressed... I went with 4 oz per k on my 2.5" northern mix and was able to go almost 5 days between cuts... Until I applied I was cutting every two days...

I was a bit nervous because my neighbor wanted in based on me doing it. I was prepared to go it alone to test how good it was... I didn't want them to spend a couple hundred and have it not work, but I got a text this morning telling me they mowed two days ago and can't see that it has grown at all.

Thanks to all the info/folks on the board that helped me make this work...


----------



## MassHole

The problem with PGR is that you need to wait 3 weeks if you make a mistake.

Your blades dull and tore the tips of the grass? You need to wait to it to come out of regulation to mow it off.
You have fungus? Need to add fungicide and can't grow it out for 3 weeks.
Seed heads below your HOC? Need to wait for it to grow out, and you are left with a brown tinge.

I'll probably do it again, but after my Midnight KBG is done seeding.


----------



## mribbens

Thick n Dense said:


> PgRs are awesome! Amazed by this product!
> Adds a dark green plus density to the grass.
> This was cut at 2 and 3/4 last night... ive never been able to get it below 3" without scalping.
> I may try for 2 1/4" tommorow.
> I mixed enough for the front for my first app and went but had some leftover so i went around the fence line with it. Definitly 100% magic.
> 
> I agree with posters that Ill never do lawn care without this.
> I wonder if fert companies put this out with their mixes. Makes sense for a better looking lawn but literally takes business away from the cutting business...
> 
> When does the rebound kick in if applied at .4 oz rate?
> 2 weeks or 3?


Grass looks great, and I agree, I will never do lawn care w/o PGR again, it has taken me from constantly thinking about a small window to cut the lawn, due to awful Midwest weather, to having a 3-4 day window now to mow. This has allowed me to go almost 5 days in between mows, unheard of during the spring flush. Also spoon feeding the lawn with liquid iron and lighter rates of granular ferts is much more manageable when your lawn is "on" PGR. It is almost like your lawn is now on steroids or something like that, charity mows happen much more often, it's just a great product.


----------



## Thick n Dense

@MassHole 
Yea, almost seems like duller blades become blantantly obvious while on PGRs.

@mribbens 
Steriods right? Feels like cheating for sure.

Is there any real downside feom missing the reapp window? Besides more mowing.


----------



## Thick n Dense

Anyone notice that the greenup effect last longer then the growth suppression?

Like the plant is stocked up on clorophyll?

I put down a 3 week rate but going on week 4. Was wondering if this is typical?


----------



## GoPre

Been using PGR for awhile now, but never with FAS. I am reapplying tomorrow with FAS, what rate do you guys typically prefer? I looked back and I see 4 oz/K, but that seems to be with Ferromec. Thanks guys.


----------



## ericgautier

@GoPre are you using this FAS or something else?


----------



## GoPre

This stuff...but looks identical.

https://www.amazon.com/gp/product/B007ODUNJ4/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1


----------



## mytmouse

So I am intrigued about using PGR, I've got TTTF, not nearly as lush and full as I'm sure most in this thread. But I was wondering if it was worth me trying it coming out of Summer before I reseed this Fall or just wait until Spring. Also, I see a lot of people apply it with iron. Is that just to combat the potential for discoloration? Or just the visual green up?


----------



## krusej23

Is there anything wrong with running pgr 1 time then taking a couple weeks off right now so some spots can fill in and then hit it again with pgr? I guess is there anything wrong with taking a couple weeks off between pgr applications?


----------



## ericgautier

krusej23 said:


> Is there anything wrong with running pgr 1 time then taking a couple weeks off right now so some spots can fill in and then hit it again with pgr? I guess is there anything wrong with taking a couple weeks off between pgr applications?


I have done this in the past w/o any issues. :thumbup:


----------



## ryeguy

krusej23 said:


> Is there anything wrong with running pgr 1 time then taking a couple weeks off right now so some spots can fill in and then hit it again with pgr? I guess is there anything wrong with taking a couple weeks off between pgr applications?


Only downside is you will see rebound (accelerated growth) for a period of time when it wears off.


----------



## krusej23

ryeguy said:


> krusej23 said:
> 
> 
> 
> Is there anything wrong with running pgr 1 time then taking a couple weeks off right now so some spots can fill in and then hit it again with pgr? I guess is there anything wrong with taking a couple weeks off between pgr applications?
> 
> 
> 
> Only downside is you will see rebound (accelerated growth) for a period of time when it wears off.
Click to expand...

I'm definitely seeing that right now in spots.


----------



## ryeguy

So does anyone here to anything differently during these hot months, app rate wise? Or is there any reason to pause apps during the heat?


----------



## g-man

When drought gets bad, I back off the rate of pgr and nitrogen. I'm currently not applying any. Heat/drought are natural growth regulators too.


----------



## MMoore

how do you guys deal with suppression going into winter dormancy?
push pgr right into the grass going dormant for winter? or do you let it go through the full rebound?


----------



## MassHole

MMoore said:


> how do you guys deal with suppression going into winter dormancy?
> push pgr right into the grass going dormant for winter? or do you let it go through the full rebound?


I plan to stop PGR after seeding. My last app will be 7 days before seeding.


----------



## g-man

Last year, I intentionally did this. I applied in late Sept and then we got a cold snap that stayed. The grass barely grew. I did not like it.

I think a better approach is to go half rate before stopping to avoid rebound.


----------



## Pete1313

MMoore said:


> how do you guys deal with suppression going into winter dormancy?
> push pgr right into the grass going dormant for winter? or do you let it go through the full rebound?


I've done it both ways, and this year I think I will time the last app to go down around 1-2 weeks before my average first frost. I've referenced it before that during some research from Ohio State, they observed earlier spring green-up when using trinexapac-ethyl the previous fall.

I apologize as some links in these threads might be dead. If I can find new links to the articles I will update.
https://thelawnforum.com/viewtopic....hilit=Trinexapac+ethyl+spring+green+up#p24829
https://aroundtheyard.com/forums2/viewtopic.php?t=21370#p294264

Here is a greencastinline article listing some of the benefits of fall applications of primo maxx(although targeted to putting greens).
http://www.greencastonline.com/techarticle.aspx?gcaid=170761

Here are some screenshots from some OSU field research with TE on wear tolerance of KBG in 2009 where they noted 


> In both May 2008 and May 2009, several months after the last TE application made the previous September, label rate TE appreciably enhanced spring green-up and turf quality
> 
> In May 2008, several months after the last TE application made the previous September, all TE treatments displayed enhanced spring green-up and turf quality
> 
> In May 2009, several months after the last TE application made the previous September, both rates of Primo Maxx and the high rate of Governor displayed enhanced spring green-up and turf quality





> TE applied in the fall expedited spring green-up the following year.


----------



## MMoore

thanks Pete.

im specifically using Aneuw PGR which isn't a TE app. it is a prohexadione calcium AI. not that I really know the difference on a scientific level.


----------



## Thick n Dense

It may sound like blasphemy but I'm getting busy with other projects around the house and want to limit applications.

Can I mix Iron + PGR with prodiamine?

I know their pathways are different but the idea is that the prodiamine will eventually wash off into the soil.

Im willing to forgo iron in the place of prodiamine if neccassary.

Thanks


----------



## MMoore

not ideal, but you can try a jar test and make sure they stay in solution.

do you use a surfactant with your pgr? if you do I wouldn't suggest doing the prodiamene at the same time.


----------



## g-man

Pgr has a sticker to it. I don't think mixing prodiamine that degrades with uv is a good idea.


----------



## mribbens

Going to get this post going again, apologies if this has been covered already. My question is with the timing of the last PGR app of the season. I am nearly at the WI/IL border, 60 miles N of Chicago. My current PGR app, according to the GreenKeeper app wears off on 9/10. I plan to apply my next, (maybe last?) app on 9/8, Sunday. First frost in my area is historically been Oct 5-15. Should my app on 9/8 be my last of the season? I will be starting my fall blitz next week, and I have irrigation.


----------



## Pete1313

mribbens said:


> Going to get this post going again, apologies if this has been covered already. My question is with the timing of the last PGR app of the season. I am nearly at the WI/IL border, 60 miles N of Chicago. My current PGR app, according to the GreenKeeper app wears off on 9/10. I plan to apply my next, (maybe last?) app on 9/8, Sunday. First frost in my area is historically been Oct 5-15. Should my app on 9/8 be my last of the season? I will be starting my fall blitz next week, and I have irrigation.


@mribbens, it can be a debatable topic when to stop PGR apps in the fall. If you read a few posts above, I've done it a few different ways.
https://thelawnforum.com/viewtopic.php?p=208580#p192392
I'm in the same climate as you, and my last apps of the season the past years were

10/17/2015

10/1/2016

9/30/2017

9/8/2018

There are many benefits of fall primo applications according to research. Many of those benefits will be noticed the next spring. This year I'm going to go back to trying to time one last app after our average first frost like I did in 2015, even later then I mentioned in the previous post, and here is why. In 2016 I sold my previous home in Mt. Prospect in spring, but one thing I noticed that year was just how good the turf looked that spring, especially early in spring. Looking thru my notes I noticed how late I applied primo the previous year. I was also hitting it with aggressive amounts of ammonium sulfate in fall 2015 due to an aggressive sand topdressing, but my last N app was also on 10/17/2015. Here are some pictures from spring 2016. I apologize for the hazy pics, my phone camera was going out at the time. Note the early green up, especially for bewitched KBG. HOC was 9/16" early on, but bumped it up to 1" for the closing.

3/31/2016 HOC 9/16"


4/13/2016 HOC 9/16" 






4/25/2016 HOC 1" 




I didn't like what I did this past year by stopping on 9/8 and letting it rebound. Color was lighter than I am used to early this spring. I personally would at least try and plan one more app after the 9/8-9/10 one you have planned.


----------



## g-man

Last year I did my last application at 06Oct. Temps dropped below normal and my grow stopped drastically. I think a half my normal rate would be better and no later than 15sep (for my weather).


----------



## mribbens

@g-man @Pete1313 Great info men!!

So with this info, thinking I will plan one more PGR app on 9/29, .5oz/M. After reading many of your posts about your journals I have been applying PGR at .5oz/M, with liquid iron included at 4oz/M, that has been a good place for me with supression, lasting 3 weeks each app. I will adjust if we are having a warm September and an extended growing season, with possibly 1 more app in Oct if weather permits.


----------



## MassHole

Pete1313 said:


> @mribbens, it can be a debatable topic when to stop PGR apps in the fall. If you read a few posts above, I've done it a few different ways.
> https://thelawnforum.com/viewtopic.php?p=208580#p192392
> I'm in the same climate as you, and my last apps of the season the past years were
> 
> 10/17/2015
> 
> 10/1/2016
> 
> 9/30/2017
> 
> 9/8/2018
> 
> There are many benefits of fall primo applications according to research. Many of those benefits will be noticed the next spring. This year I'm going to go back to trying to time one last app after our average first frost like I did in 2015, even later then I mentioned in the previous post, and here is why. In 2016 I sold my previous home in Mt. Prospect in spring, but one thing I noticed that year was just how good the turf looked that spring, especially early in spring. Looking thru my notes I noticed how late I applied primo the previous year. I was also hitting it with aggressive amounts of ammonium sulfate in fall 2015 due to an aggressive sand topdressing, but my last N app was also on 10/17/2015. Here are some pictures from spring 2016. I apologize for the hazy pics, my phone camera was going out at the time. Note the early green up, especially for bewitched KBG. HOC was 9/16" early on, but bumped it up to 1" for the closing.
> 
> 3/31/2016 HOC 9/16"
> 
> 
> I didn't like what I did this past year by stopping on 9/8 and letting it rebound. Color was lighter than I am used to early this spring. I personally would at least try and plan one more app after the 9/8-9/10 one you have planned.


Amazing results @mribbens.

I used PGR on Aug 31 at 0.4 oz/K on my KBG, then slit seeded on Sept 5.

The means I should be coming out of regulation around now (i'm starting to see some rebounding in some spots).

The recommendation is to use PGR again 4-6 weeks after germination, putting me at around Oct 15 at the earliest, if not later. I think I won't be able to use it again this year since that will be my first frost window. Thoughts?


----------



## mribbens

@MassHole Well, I am with you as we are having a warm few weeks right now and my next app is now this Sunday possibly if weather allows. That would get me out to 10/13, so depending on how the next 2 weeks go 10/13 could be my last app. I did apply 29-0-4, half rate, last Saturday and the grass is looking like it needs to be cut after 3 days or so, even under good regulation. We had 7 inches of rain from last Monday to Friday am last week, and now it has been sunny and low 80's M and T. The grass is growing crazy everywhere, so I need to stay under PGR, or I won't be able to keep up. Currently mowing every Sat or Sun and Wed now. Thoughts?


----------



## MassHole

mribbens said:


> @MassHole Well, I am with you as we are having a warm few weeks right now and my next app is now this Sunday possibly if weather allows. That would get me out to 10/13, so depending on how the next 2 weeks go 10/13 could be my last app. I did apply 29-0-4, half rate, last Saturday and the grass is looking like it needs to be cut after 3 days or so, even under good regulation. We had 7 inches of rain from last Monday to Friday am last week, and now it has been sunny and low 80's M and T. The grass is growing crazy everywhere, so I need to stay under PGR, or I won't be able to keep up. Currently mowing every Sat or Sun and Wed now. Thoughts?


Apply this weekend and re-eval in Oct. I'll talk with you in 4 weeks!!! :lol:


----------



## mribbens

MassHole said:


> mribbens said:
> 
> 
> 
> @MassHole Well, I am with you as we are having a warm few weeks right now and my next app is now this Sunday possibly if weather allows. That would get me out to 10/13, so depending on how the next 2 weeks go 10/13 could be my last app. I did apply 29-0-4, half rate, last Saturday and the grass is looking like it needs to be cut after 3 days or so, even under good regulation. We had 7 inches of rain from last Monday to Friday am last week, and now it has been sunny and low 80's M and T. The grass is growing crazy everywhere, so I need to stay under PGR, or I won't be able to keep up.  Currently mowing every Sat or Sun and Wed now. Thoughts?
> 
> 
> 
> Apply this weekend and re-eval in Oct. I'll talk with you in 4 weeks!!! :lol:
Click to expand...

I put down my PGR Tuesday and the GDD takes me out to 10/8, so we will evaluate the weather over the next 2 weeks. We are supposed to stay warm and wet here in the Northern Great Lakes region, which could keep us growing strong through Oct.


----------



## Thick n Dense

Sprayed today!

Iron, pgr, urea and a dash of kelp... (is kelp foliar uptake or roots?)
Cant wait to see that dark green come on


----------



## Harts

@Thick n Dense you're going to love the results!


----------



## MassHole

mribbens said:


> I put down my PGR Tuesday and the GDD takes me out to 10/8, so we will evaluate the weather over the next 2 weeks. We are supposed to stay warm and wet here in the Northern Great Lakes region, which could keep us growing strong through Oct.


Did you seed?


----------



## mribbens

I did a little mini reno on a North section, maybe 250 sq ft, it has been great, coming in nicely. I have not used PGR on the new grass though, just fast release N. I have had 9 inches of rain the past 2.5 weeks, and temps in the high 70's and low 80's.


----------



## krusej23

I put my application of PGR down on Sept 19th and I purposely split my backyard up so that I could see the clear difference. Here is the difference. I am liking the slow down of growth but it or the tenacity seems like it has damaged the grass a little and it looks off colored compared to the control grass. The pgr application was .55oz per 1000 on a mix of tttf, prg, and kbg.


----------



## Naidu

Interesting was tenacity was applied to both?


----------



## Thick n Dense

Harts said:


> @Thick n Dense you're going to love the results!


Turned out great but then decided to aerate ... oops :shock: 
Im sure ittl be fine but take longer for the plugs to dissapear.


----------



## krusej23

Naidu said:


> Interesting was tenacity was applied to both?


Not a true experiment because tenacity was only applied to the pgr side because that side had a lot more weeds in it.


----------



## krusej23

Does the stiffness of the blades of grass go away when the PGR wears off? I seem to have more stiffness or stickiness to the blades more than the last 3 times I have applied it. With my riding mower it seems to roll the blades over and then some spots don't like coming back up. Any solutions or just wait?


----------



## Thick n Dense

krusej23 said:


> Does the stiffness of the blades of grass go away when the PGR wears off? I seem to have more stiffness or stickiness to the blades more than the last 3 times I have applied it. With my riding mower it seems to roll the blades over and then some spots don't like coming back up. Any solutions or just wait?


If been seeing this too. Applied pgr then aerated... grass is still folded over and havent perked up... should I hit it with fast N?


----------



## MassHole

So I am now 5 weeks after slit seeding Midnight and Bluebank, 3.5 weeks after germination, 6 weeks post PGR, and getting cold at night.

Been mowing at 3" often to encourage tillering. No idea what to do on PGR...


----------



## mribbens

MassHole said:


> So I am now 5 weeks after slit seeding Midnight and Bluebank, 3.5 weeks after germination, 6 weeks post PGR, and getting cold at night.
> 
> Been mowing at 3" often to encourage tillering. No idea what to do on PGR...


According to my GDD I had over 3 weeks of regulation, serious regulation on my grass. I applied on 9/22, @ .5oz/M and we had record rains, super cold temps and I got hit with rust pretty bad. It is taking forever to grow out of it. We are forecasted for some mid 60's so hopefully the rebound will get going and I can grow out of the rust.


----------



## ThePowerTool

I was previously skeptical of PGRs, but I have to admit that I wasn't aware of the additional benefits (like better color, turf density, etc..) until I joined this forum. Now I'm thinking that this might be a tool I should be using. I'm still not sure, though.

How dramatic are the improvements to turf density in your standard northern mix yard which doesn't have many spreading grasses? Will it help clumping grasses like fescue fill in small bare spots? My yard is a bit thin, and in some places you could even call it patchy. I also watched a Lawn Tips vid where he said you shouldn't apply it to patchy yards because it would slow new growth too much which kind of seemed to contradict the stuff I've read in this thread.


----------



## MassHole

ThePowerTool said:


> How dramatic are the improvements to turf density in your standard northern mix yard which doesn't have many spreading grasses? Will it help clumping grasses like fescue fill in small bare spots? My yard is a bit thin, and in some places you could even call it patchy. I also watched a Lawn Tips vid where he said you shouldn't apply it to patchy yards because it would slow new growth too much which kind of seemed to contradict the stuff I've read in this thread.


I was the same way. I apply it to my fall seeded areas in the spring to fill in.

My biggest tip is to go light (0.4 oz / gallon / K or less) and don't apply until the lawn is out of regulation.
Add iron for color, and fungicide for ... duh... fungus.

I have Midnight and Bluebank KBG and plan to apply it after my third mowing.


----------



## Green

MassHole said:


> My biggest tip is to go light (0.4 oz / gallon / K or less) and don't apply until the lawn is out of regulation.


I agree with doing light apps. I think I was doing 1/3 of full rate last year, and that was for high cut turf.

But what did you mean by "don't apply until the lawn is out of regulation"? Generally, the goal is to keep it regulated, and not have it surge grow in between apps. In fact, I came up with a method that avoids the rebound growth that normally occurs when you stop the apps.


----------



## Scagfreedom48z+

I haven't had much luck applying PGR at or close to the designated amounts. I have to go as far down as .25 fl oz per gallon or my grass looks like crap(brown/yellow). I use my spreadermate and actually speed up my walk more than usual out of fear of having this happen with my apps.


----------



## Pete1313

This clip was taken from some of Bill Kreuser's work that is few years old now(the GDD numbers have been revised and upped a bit since this research), but it was noted that the best visual turfgrass quality on KBG was at the .20 fl oz/M rate. The trial had consisted of rates of .10, .20, and .40 fl oz/M each applied at 100, 200, and 400 GDD base 0c. I personally have had good success staying in the .20-.30 oz/M range depending on the time of year and reapplying based on his current KBG GDD reapplication intervals of 274-287 GDD base 0c for those spray rates. Too high of a rate or reapplying too soon will give you that over regulated/shredded leaf tips look.


----------



## MassHole

Green said:


> But what did you mean by "don't apply until the lawn is out of regulation"? Generally, the goal is to keep it regulated, and not have it surge grow in between apps.


I applied it accidentally after 2 weeks and had browning. Going forward, I plan to apply during peak growing times to thicken up, and not continuously...

I still don't understand how GDD works for my zip and how to calculate it...


----------



## ScottW

MassHole said:


> I still don't understand how GDD works for my zip and how to calculate it...


GDD modeling is based on temperature. You take the average temperature for a given day, in Celsius, and add it to the previous day's average temp. These numbers accumulate in a running total towards your defined threshold. The hotter the weather the sooner your threshold is reached. The count is reset to zero whenever you put down a new application of PGR.

To track this stuff you either need to input your weather data manually and do your own calculations  :wacko:  :bd: or use an automated tracker. Greenkeeperapp has one, and there's also a Google sheet created by a forum member (g-man IIRC) that will track it. Both rely on knowing your location, which they use to pull weather data from Dark Sky or the like and compute your GDD numbers.

I got some practice using greenkeeperapp last year to track my fert, fungicide, and pre-em applications. This will be my first year using PGR on my TTTF lawn, excited to see how that goes.


----------



## g-man

^+1

There was work by Dr. Bill Kreuser that basically developed a correlation with GDD with how long the suppression and rebound last. The life of the product in the plant is shorter when the weather is warmer. Instead of just guessing and applying every 3weeks, the GDD gives a way to adjust the frequency to get more consistent control.

You need to ease into it. The first application can be at half the normal rate and then increase into it. My typical rate is 10mL/ksqft.


----------



## BDalton

I know for previous seasons someone had a thread on splitting PGR to help lower the entry cost. Is that still offered anywhere on here?


----------



## corneliani

ScottW said:


> This will be my first year using PGR on my TTTF lawn, excited to see how that goes.


When do you plan on doing your first app? I'm thinking of utilizing it on my TTTF portion this year as well. I was impressed with what it did to my bermuda last year.


----------



## Pete1313

BDalton said:


> I know for previous seasons someone had a thread on splitting PGR to help lower the entry cost. Is that still offered anywhere on here?


@BDalton, here is the thread you are looking for.

https://thelawnforum.com/viewtopic.php?p=239234#p239234


----------



## ScottW

corneliani said:


> ScottW said:
> 
> 
> 
> This will be my first year using PGR on my TTTF lawn, excited to see how that goes.
> 
> 
> 
> When do you plan on doing your first app? I'm thinking of utilizing it on my TTTF portion this year as well. I was impressed with what it did to my bermuda last year.
Click to expand...

I was thinking of starting after either the second or third mow once the spring growth begins. Maybe start after the second mow and ease into it with a lower rate on the first app as g-man suggests. Never done this, not an expert.

In past years my spring growth has been so friggin fast I'd have to mow every 3 days to not violate the 1/3 rule. If it rained and I couldn't get a mow in around my work schedule and went a week between... fuhgeddaboudit. If the PGR helps manage this I'll be happy, not to mention the other benefits on turf quality.

Planning to stay at the 2" HOC I ran after last fall's partial reno, or at least seeing how well that will work or how long I can maintain that (with help of PGR) through spring, before letting it lengthen a bit with summer heat. Not entirely sure what I'm signing up for, but it should be fun. Down south you will have a head start, so definitely report on what rate you're using on TTTF and at what HOC. Seems like most people in this thread have KBG lawns so the added data would be helpful.


----------



## BDalton

@Pete1313 Thanks!


----------



## ThePowerTool

I know it's common to mix FAS with PGR, but has anybody tried adding MicroGreene? I have some left over from the bio-stim pack I bought last year.


----------



## 440mag

g-man said:


> Ammonium sulfate helps the leaves absorb more product.


Howdy, g-man! Perhaps you or anyone can answer this question:

Is the "DSM Ammonium Sulfate" I found at my local Rural King (thank y'all for that tip, btw! :thumbup: going to accomplish anything similar to the "Ammonium *Laureth* Sulfate" that I just noticed is the only ingredient in the bottle of Simple Lawn Solutions "Liquid Soil Loosener" that we just took delivery of?

I guess I am wondering if I can achieve any soil loosening results by dissolving the RK DSM Ammonium Sulfate and spraying it on my lawn?

I'll try and add some photos as soon as I am able ...


----------



## g-man

Not even close. Ammonium sulfate (21-0-0) is the fertilizer, but it will not do any soil loosening.

ALS (Ammonium Laureth sulfate or Ammonium Laurul sulfate) is an anionic surfactant. Surfactants are compounds that lower the surface tension. It is common in soaps (eg. baby shampoo).


----------



## 440mag

g-man said:


> Not even close. ...


I used to hear those words a lot on first dates, back in high school. Sigh. :lol:



g-man said:


> ...
> ALS (Ammonium Laureth sulfate or Ammonium Laurul sulfate) is an anionic surfactant. Surfactants are compounds that lower the surface tension. It is common in soaps (eg. baby shampoo).


Ahhhhhh-ha. Not only does that likely explain why Baker used to include it many of his DIY "Yarden recipes" but, now you have me thinking of adding a tablespoon or two of dollar store baby shampoo to some of my backpack sprayer applications .... hmmmmm


----------



## ryeguy

If I want to avoid overregulation, how much of a gap should there be between tnex and propiconazole apps?


----------



## g-man

I'm sure there has to be a study (might not be published) around this. https://greenkeeper.blog/2020/05/05/pgr-gdd-models-v2-0/


----------



## bernstem

ryeguy said:


> If I want to avoid overregulation, how much of a gap should there be between tnex and propiconazole apps?


I don't know of any specific study. I try to time any DMI fungicide to be at the half way point of the re-application interval. If you use a 300 GDD interval, apply at ~150. If it is a strict time based interval, use the half way point. If I feel the lawn really needs a DMI, I also have no problem applying when the lawn needs it even if it is at the same time. I also tend to avoid DMI fungicides in hotter weather as the risk of turf damage is higher and I don't want to pay extra for the newer DMIs with less heat issues. Look at the price of Briskway (1800.00 per gallon).


----------



## corneliani

Interested to get your thoughts on bringing my turf out of regulation for the summer (or should I dare continue straight through?).. and how to best proceed.

I'm using TNex for the first time this year on my TTTF portion, mainly to help drive deep roots on this new renovation. I've started at 0.6oz/M in mid March and have continued at 0.5oz/M using the greenkeeperapp. This past weekend I reduced the rate to 0.25oz thinking i'll step things down gently (plus I put out my Azoxy & Prop fungicide app as well). Is this logical, or should I just quit cold-turkey? I'm seeing weird growth the past few days... long stragglers scattered throughout the yard... that i"m assuming is PGR related. What's a good course of action? Being in the deep south BP on TTTF is a guarantee, it seems.


----------



## jha4aamu

Pete1313 said:


> This clip was taken from some of Bill Kreuser's work that is few years old now(the GDD numbers have been revised and upped a bit since this research), but it was noted that the best visual turfgrass quality on KBG was at the .20 fl oz/M rate. The trial had consisted of rates of .10, .20, and .40 fl oz/M each applied at 100, 200, and 400 GDD base 0c. I personally have had good success staying in the .20-.30 oz/M range depending on the time of year and reapplying based on his current KBG GDD reapplication intervals of 274-287 GDD base 0c for those spray rates. Too high of a rate or reapplying too soon will give you that over regulated/shredded leaf tips look.


my t-nex app rates were always between the .75oz/k - 1oz/k range and i have noticed that shredded leaf tip in several areas. i plan on using ~280 gdd interval for my t nex apps now and dropping it to .3oz/k going forward, and hopefully that address that leaf tip issue.

on the topic of reapplication/over regulation, how would one know when to reapply the pgr after an initial app of 1oz/k? i assume the recommended 300 gdd interval is based on a proper app rate of between .2oz - .3oz. but is there info/data on reapplication interval if you feel you have over applied the previous app?


----------



## ISU

Fellas- put down my first app of PGR ever (anuew) and literally 5mins after Mother Nature decided to put down some heavy rain for 10mins straight....my question is the following, I'm a safe to assume that I just waisted product and safe to reapp or should I still wait next 3 weeks to reapp? mainly wondering if I'm okay to reapp as soon as I can again. I had checked the forecast prior to putting down PGR app and wasn't supposed to rain until midnight which would have given me at least 7 hrs of timeframe for product to sit on the leaf but apparently Mother Nature had different plans (or wheather man got it wrong once again).

Below is image to give an idea of how much rain we had.


----------



## Greasmatta

Hello all.

I have ordered some PGR and have some questions. 
Here in Sweden it's quite hard to get hold of chemicals for the lawn if you are not an professional. 
But I manage to order some PGR from Poland. 
It is Syngenta made with 25% of trinexapac-ethyl. Noticed that Primo Maxx has 12.5%.

What do you think of application rate. 
The Syngenta label mentions 
0.3-0.6 litre/acre (metric) depending on Cultivation
Using Google translate from polish.

For "Spring barley, Winter barley, Oats, spring wheat, Winter wheat, Winter triticale, Winter rye"

Nothing about lawns.

What du you think using half of Primo Maxx max application rate as max rate for Syngenta 25%. 
Because it has double the amount of trinexapac-ethyl.

Does that sound logical?

Is it ok to start using PGR in any time of growing season?

Cheers!


----------



## g-man

That sound very logical.


----------



## Greasmatta

Ok thank you.
Do you think it is ok to start anytime in growing season or is it 2nd mowe in spring that is the starting point. 
Sorry for complete noob questions


----------



## bernstem

@Greasmatta You can start at any time, though you will see the most benefit in regards to stress resistance, density, and tillering if you start earlier. General recommendation is to start low and increase dose as needed. For low cut grass, with Primo, 0.3-0.4 seems to be the most common dose. For typical lawn height, 0.4-0.6 is more likely where you want to be.


----------



## Greasmatta

Great. Cheers!


----------



## ScottW

My first year using PGR (T-NEX). Lawn is mostly TTTF with some KBG and some patches of what is probably K31 (front lawn has never been fully reno'ed, but probably will this fall). Mowed at 2.5" HOC in spring and will be looking to raise it to 3" and then 3.5" (highest my mower will go) very soon.

I'm fairly certain I have reached the point of over-regulation.
First app was at the 0.3 oz/M rate on May 14. Followed greenkeeper GDD target for the 0.3 oz rate of 287.
GDD target reached and next app at 0.5 oz rate on May 30. On this day, before spraying, the lawn looked pretty good (pic below). GDD target for the 0.5 oz rate is 317.
A week later on June 6 I noticed some white mycelium and dollar spot lesions in just a few places, but overall the lawn looked good. Sprayed propiconazole on June 7. You can probably tell where this is going.
I made another app of T-NEX at the 0.5 oz rate on June 16, which was 2 days past the GDD target.
Yesterday I noticed the lawn has gotten funky. It's a more muted green with gray/yellow tinge when viewed at certain angles.

I had read of the potential for over-regulation with PGR + DMI fungicides, but I think I have now experienced it first hand. :lol: 
But I honestly don't know how much of the over-regulation is from the addition of the propiconazole, or if I'm simply using too much PGR too often.

I question whether I should be sticking firmly to the GDD targets on greenkeeper. Those are based on clipping yield suppression rather than any of the qualitative improvements (density, color, stress management etc). The GDD target is when maximum clipping suppression has been reached, 45-50% or so. The modeling shows that when going past the GDD target, the level of suppression gradually decreases for a good while before going into proper rebound (faster than unregulated) growth.
For example, in this weather applying on/near the GDD target means an app every 2 weeks. But a week later than the target date (150% of the original targeted GDD interval) the model still shows 20% suppression. So it won't be maximally suppressed but will still be growing slower than unregulated grass.

Trying to figure out exactly how to approach this but I need to either extend my intervals, or back off the rate, or both.
FWIW, I have been mixing in either FAS or Main Event with my PGR and have also made occasional spoon feedings of N at 0.25 lbs/M, but am still at just 1.14 lbs N total for the year so far. Could probably use some more N but I don't want to go nuts heading into hotter weather.

Thoughts/comments from the PGR cognoscenti?

May 30:









June 19 (different angle but you get the idea):


----------



## Pete1313

Oh I've been down this road with t-nex and propiconazole. Couple quick questions? What rate of propiconazole? Did you leave it on the leaves or water it in? Did you tank mix anything with it?

I personally stick to the GDD model for reapplying t-nex. More consistent suppression.


----------



## ScottW

I used 2 fl oz/gal/M of propiconazole 14.3, which is the higher rate because I actually had DS lesions in the lawn. (The lower preventative rate for this product would be 1 oz/gal/M)
That was tank mixed with 1 oz/gal/M of dissolved granular urea for a tiny bit of N.
It was sprayed in the evening and left on the leaves overnight and the entire next day (36 hours or so; high temp on that day was 82F) before I ran sprinklers on the second morning afterwards.


----------



## Pete1313

@ScottW, looking back thru my spreadsheets from 2018.

5/4/18 - T-nex @ .4oz/M
5/26/18 - Propiconazole 14.3 @ 2 oz/M
Left propiconazole on the leaves for foliar. 90°+ temps around the time applying propiconazole. No good, overregulation. Grass alittle unsightly, did not have to mow for a while.

7/1/18 - T-nex @ .3 oz/M tank mixed with propiconazole @ 1 oz/M. 
Not sure why I tank mixed them, left on leaves, upper 80's temp. Similar issue as before, just not as bad.

9/8/18 - T-nex @ .13 oz/M also tank mixed with propiconazole @ 1 oz/M.
Left on leaves, mid 70's temp. Minimal issues, but still slight overregulation.

This year
5/30/20 - T-nex @ .3 oz/M
6/12/20 - T-nex @ .2 oz/M
6/18/20 - Propiconazole @ 2 oz/M
I dropped the last T-nex rate down in anticipation of the Propiconazole. This time with the propiconazole i immediately watered it into the soil with .2" of irrigation. Temps are mid 80's. Growth is good right now, but we will see what the propiconazole does to slow it down.

I think your rates were too high on the T-nex when combined with later using propiconazole. I'm also not sure if putting propiconazole on as a foliar amplifies the effects when the lawn is under T-nex regulation. I played it safer this year by dropping the T-nex rate beforehand and watering in the propiconazole. We will see how my experiences go this year. The good news is your lawn will recover.


----------



## ScottW

@Pete1313 Thanks, had not really considered watering in the PPZ before, but I can see how that might help. I'm coming up on the end of that 2-week coverage window so I'll reassess whether I need another app. I also have some Cleary's (thiophanate-methyl; Group 1) that I could run instead if necessary.

I will definitely be backing off the T-NEX rate regardless. Looking back, I was pretty happy with the subjective quality of the lawn at the 0.3 oz rate and that's more important to me than clipping yield suppression. Even before applying PPZ, growth had slowed way down with the 0.5 oz rate, so I probably should have known better. Live and learn, at least it should recover.


----------



## g-man

Propi does have a regulation effect to it. There is a new feature on the greendkeeperapp that displays the combined effect of both pgr and dmi fungicides. But it is part of the premium $$$ package. I think the premium is too expensive for us.


----------



## Pete1313

I took a screenshot of this from some greenkeeperapp email/post, but is the best we can gather without a premium membership.


----------



## DiabeticKripple

new to the PGR game, just got my anuew today.

i have seedlings that are about a month old, and i just seeded some areas that didnt take.

i would like to spray tenacity again, PGR and PPZ to clear up some powdery mildew and leaf spot.

think the seedlings can take it? or should i just wait until they are more mature?

for reference you can check my journal, i just have spots of seedlings and the rest of the lawn is going crazy with all the water.


----------



## ScottW

@DiabeticKripple Keep in mind that propiconazole _is_ a PGR (see above).
This is my first year using T-NEX and I have no experience with Aneuw. I have over-regulated my turf from using both T-NEX + PPZ (even though they were applied a week apart) because I didn't realize how severely the two would tag-team the lawn. This was on my mature turf only, because I've avoided spraying my spring seeded areas when applying the PGR.

PPZ can actually help establishment and is fine on new seedlings. It will slow their top growth a bit, but encourage rooting & tillering, and new seedlings need to be protected from fungus. Therefore, the PPZ can be sprayed everywhere.

Tenacity, if you're applying to extend the pre-m activity in your overseeded areas, it's fine. Not sure I'd blanket spray it over the mature turf as well, just because the silvering is unsightly and you're also pondering hitting it with PGR.

If most of the lawn is growing like crazy, you could apply PGR as well, but caution is the word of the day here. Either use a very low rate, or just hold off while PPZ is active. Maybe see how much suppression you get from the PPZ and go from there. You can always add things to your lawn but it's difficult to remove them after you spray.


----------



## bernstem

Propiconazole has phytotoxic effects as long as it is in the plant. If you apply in 70 degree weather, but a week later it hits 95 you can see phytotoxicity from the heat since the Propiconazole is still in the grass. I have switched to the FRAC 7 fungicide Velista in the heat because of this. Another option are the "cooling" DMIs, but they are expensive and might just be marketing.


----------



## DiabeticKripple

a HOT day here is 80f. Doesnt ever really get above that and humidity stays low around 40% so i dont really get the heat stress you mericans get.

Ill spray the PPZ first and wait a bit before applying the Aneuw. Clear the issues up before starting the regulation.


----------



## Jp6940

I have a 5lb jug of Apogee. Is this what you are referring to as a PGR? I purchased it for a good price for the early summer as I had a lot of poa a and seed heads. Never used it
Can I use this? Is this what you are referring to as a PGR? I just didn't see any names mentioned.


----------



## JSS

How soon would you consider applying a pgr to new seedlings? I have just renovated 12k ft with Bluebank, Bewitched, and Mazama 2.5 weeks ago. The seedlings have just exited the pout stage and are growing nicely. I mowed at 7/8 today and removed about 3/8. 
I got excellent coverage with very few spots that need to fill in. Should I wait until spring for pgr or apply after a few more mowings?


----------



## g-man

I waited until spring after my reno. I just don't like the risk of slowing top grow and some fungus developing (eg. Rust).


----------



## g-man

I waited until spring after my reno. I just don't like the risk of slowing top grow and some fungus developing (eg. Rust).


----------



## JSS

Added pic to show density


----------



## JSS

Thanks gman. I'll just use some propiconazole this fall &#128077;


----------



## turfnsurf

The good thing about learning is that you know better. The downside is if you find out too late.

I intend to seed tomorrow, since I am on the back end of my optimal window.

And since I didn't know about PGR before hand, and I don't have any PGR on hand, it looks like I will miss the opportunity to use it.

I intend to go over to the Marketplace forum to see if I can get a few ounces. Is it worth it at this point, or should I just wait until the spring to use it?

And if it is too late, I just need to be mindful that my grass is low enough, drop the seed, water and wait...correct?


----------



## MassHole

JSS said:


> How soon would you consider applying a pgr to new seedlings? I have just renovated 12k ft with Bluebank, Bewitched, and Mazama 2.5 weeks ago. The seedlings have just exited the pout stage and are growing nicely. I mowed at 7/8 today and removed about 3/8.
> I got excellent coverage with very few spots that need to fill in. Should I wait until spring for pgr or apply after a few more mowings?


I am waiting 2 months after germination.

I seeded Midnight on May 20, had germination complete by June 20, sprayed August 28.


----------



## g-man

This video from the 2020 Wisconsin Turf Field Day is really interesting. Dr. Doug Soldat shows a study of multiple PGRs at high/low rates on KBG at higher hoc. Each group was then also treated with simulated football cleats traffic. The results on the control group surprised me.

https://youtu.be/B3PZCQZ7PKM

I might need to get the neighbor kids to play with cleats on my backyard.


----------



## dwaugh

g-man said:


> This video from the 2020 Wisconsin Turf Field Day is really interesting. Dr. Doug Soldat shows a study of multiple PGRs at high/low rates on KBG at higher hoc. Each group was then also treated with simulated football cleats traffic. The results on the control group surprised me.
> 
> 
> 
> 
> 
> 
> I might need to get the neighbor kids to play with cleats on my backyard.


Yeah, It does seem strange that the best plot was the control with traffic which involved basically running a sheep's foot compactor with a tearing action over the grass. I wonder if it's the pushing in the overseeded seeds that made it look so good? I mean, the best plot involved doing something that most people think would be destructive.


----------



## g-man

@dwaugh I don't think these plots had any overseed.


----------



## SNOWBOB11

This must be why @Pete1313 always says he lets all the neighbors play on his lawn


----------



## Pete1313

SNOWBOB11 said:


> This must be why @Pete1313 always says he lets all the neighbors play on his lawn


 :thumbsup: :lol: 
Grass is meant to be played on/enjoyed!


----------



## Sinclair

Would the results of that study suggest that frequent mild mechanical injury is beneficial, such as from power raking, verticutting, dethatching, etc?


----------



## iLoveLawns

https://www.greencastonline.com/techarticle.aspx?gcaid=170761

This article talks about several benefits of PGR application during fall after the first frost. My last PGR application was on 9/3. The first freeze was last week of Oct. Based on that article does it make sense to make one light PGR application in next couple of days?


----------



## nnnnnate

I spent the last few days reading through this thread as I prepared to use PGR for the first time. I appreciate all the information and discussion. My front lawn was sodded summer 2019 and my back lawn was sodded May 2020. I did the super nitrogen blitz last fall feeding it heavy to get the seams to fill in and also did some sand leveling. I started reel mowing last fall as well.

I haven't pulled out my GM1000 yet this year since a lot of crap has blown onto the lawn that I've used my rotary mower to clean up while also cutting the grass. I'm at about 1.25" HOC right now but with the reel go at about 3/4".

*I sprayed 0.2 oz t-nex and 3 oz "Quick Green Iron" per 1000 sqft* that I got from my local farm supply store. (3.6% sulfur, 5.0% iron, comes as a liquid). I also add blue dye because I am still pretty new at spraying and need the additional help. Other than turning my shoes blue it went down well. I took off camping an hour after spraying on Tuesday morning but it rained later that night and has continued off and on since then. The lawn looks good, a bit darker green but we'll see if I notice much from the PGR. I intentionally went light on the t-nex for the first use. I've got it logged in greenkeeper and I plan to continue applying it through the season.

I got a little container of the t-nex from the guy I bought my GM1000 from last fall. I think it should last me a few more months but will be looking to purchase more in the next while I'm sure. I've got a couple neighbors that I've been chatting with about doing some chemicals on their lawns so I may have them buy and then I'll spray and keep track of when it needs to go down.

This is a reference pic of the lawn before spraying. (My father in law is skating on thin ice for his parking job...)


----------



## nnnnnate

As you can see I applied tnex on 4/13 and per greenkeeper the expected lifespan is until 5/10. This was my first time using a PGR and I'm trying to figure out when I need to reapply. I was thinking I read that people apply before its out of regulation but I couldn't remember if that was while using the GDD calculations.

Basically what I'm asking is should re-apply tnex on 5/10 (or whatever it changes to per greenkeeper as our temps rise) or should I apply BEFORE 5/10 to keep it under regulation.

Thanks.


----------



## g-man

On 10May. That day does move a bit based on actual temps.


----------



## nnnnnate

Thank you so much @g-man thats exactly what I needed to know. I do understand the date in the app will change based on temps. Tomorrow and Saturday are supposed to be 80+ (from the 60s) so I expect that date will move up at least a few more days.


----------



## Nikegolf1224

How soon can grass be mowed after spraying a pgr?


----------



## bernstem

@Nikegolf1224 For Primo (Trinexapac-Ethyl), wait 4 hours after application to mow, or wait 1 hour after mowing to apply. I do not know timing for other PGRs, but it should be on the label.


----------



## Nikegolf1224

I just applied Anuew by Nufarm. I'll have to double check the label but I should be good if Im mowing tomorrow. Also I have been recommended to start out by using the minimum dosage, which I have. Is applying the lowest app rate just to protect people from making mistakes like overlapping? I spent more time making sure my sprays were as even as possible.


----------



## Jp6940

Would Apogee (Prohexidione calcium) fall under this same category? It's 27.5%.
I purchased it to use throughout the summer.
Is that one issue you are trying to solve is heat in hot summer that stresses the turf?
I have tttf in MD


----------



## Airbender

Jp6940 said:


> Would Apogee (Prohexidione calcium) fall under this same category? It's 27.5%.


The Label clearly says "Apogee® plant growth regulator is a production management tool for producers of grass grown for seed including perennial ryegrass, Kentucky bluegrass, fine, and tall fescue". https://assets.greenbook.net/13-51-34-10-07-2017-Apogee_NVA_2016-04-080-0247.pdf

So you should be fine using it as a PGR for TTTF.

It seems to be the same ingredient as Anuew, albeit in a liquid form.

Oddly, their tag line or elevator spiel is - "Apogee is used for apple, grass grown for seed, peanut, and sweet cherry".


----------



## Kstawski

So I'm bit of a planner and thinking about fall overseed already. First year using PGR.

I know I'll slowly lower my HOC in August, but wondering the correct order of things: Do I use PGR, wait a few days, then scalp and aerate? Or does the order not really matter?

Sorry if this has been asked a bunch, I tried searching but didn't come up with anything. Thanks!


----------



## tneicna

Kstawski said:


> So I'm bit of a planner and thinking about fall overseed already. First year using PGR.
> 
> I know I'll slowly lower my HOC in August, but wondering the correct order of things: Do I use PGR, wait a few days, then scalp and aerate? Or does the order not really matter?
> 
> Sorry if this has been asked a bunch, I tried searching but didn't come up with anything. Thanks!


Here's what *I* would do:

- PGR (Trinexapac-ethyl) 
- Wait 3 or 4 days
- Aerate 
- Wait 3 days (again)
- Overseed.

Time the PGR applications in between a 72-hour window of no rain so 100% of its foliar absorbed.


----------



## tneicna

Airbender said:


> Jp6940 said:
> 
> 
> 
> Would Apogee (Prohexidione calcium) fall under this same category? It's 27.5%.
> 
> 
> 
> The Label clearly says "Apogee® plant growth regulator is a production management tool for producers of grass grown for seed including perennial ryegrass, Kentucky bluegrass, fine, and tall fescue". https://assets.greenbook.net/13-51-34-10-07-2017-Apogee_NVA_2016-04-080-0247.pdf
> 
> So you should be fine using it as a PGR for TTTF.
> 
> It seems to be the same ingredient as Anuew, albeit in a liquid form.
> 
> Oddly, their tag line or elevator spiel is - "Apogee is used for apple, grass grown for seed, peanut, and sweet cherry".
Click to expand...

Prohexidione calcium seems to be a much better fit for cool-season lawns than Trinexapac-ethyl; Prohexadione‐calcium has a small advantage in performance: most likely due to its more immediate action after application (Rademacher, 2014), it also inhibits seedhead formation in unwanted Poa annua (Beam and Askew, 2005).


----------



## Kstawski

tneicna said:


> Kstawski said:
> 
> 
> 
> So I'm bit of a planner and thinking about fall overseed already. First year using PGR.
> 
> I know I'll slowly lower my HOC in August, but wondering the correct order of things: Do I use PGR, wait a few days, then scalp and aerate? Or does the order not really matter?
> 
> Sorry if this has been asked a bunch, I tried searching but didn't come up with anything. Thanks!
> 
> 
> 
> Here's what *I* would do:
> 
> - PGR (Trinexapac-ethyl)
> - Wait 3 or 4 days
> - Aerate
> - Wait 3 days (again)
> - Overseed.
> 
> Time the PGR applications in between a 72-hour window of no rain so 100% of its foliar absorbed.
Click to expand...

Thanks for the feedback! Just curious, why wait 3 days after aerating before overseeing?


----------



## tneicna

Kstawski said:


> tneicna said:
> 
> 
> 
> 
> 
> Kstawski said:
> 
> 
> 
> So I'm bit of a planner and thinking about fall overseed already. First year using PGR.
> 
> I know I'll slowly lower my HOC in August, but wondering the correct order of things: Do I use PGR, wait a few days, then scalp and aerate? Or does the order not really matter?
> 
> Sorry if this has been asked a bunch, I tried searching but didn't come up with anything. Thanks!
> 
> 
> 
> Here's what *I* would do:
> 
> - PGR (Trinexapac-ethyl)
> - Wait 3 or 4 days
> - Aerate
> - Wait 3 days (again)
> - Overseed.
> 
> Time the PGR applications in between a 72-hour window of no rain so 100% of its foliar absorbed.
> 
> Click to expand...
> 
> Thanks for the feedback! Just curious, why wait 3 days after aerating before overseeing?
Click to expand...

Give the soil a chance to settle after being disturbed.


----------



## kay7711226

#Tagging


----------



## JerseyGreens

Quick Question:
Can we no longer change the GDD in the Greenkeeper app, and what would you guys recommend for rates on a KBG Reno coming into the first spring? This will be my first ever PGR app.

Thanks!


----------



## Jersey_diy

Wouldn't it be a good idea to apply pgr in the early evening so it is less likely to evaporate?


----------



## drcolossus11

Is there a table anywhere that has GDD recommendations based on grass type and application amount?


----------



## g-man

For all cool season lawn types at all HOC except greens heights with T-nex in oz/ksqft:


----------



## drcolossus11

@g-man Thanks!


----------



## PGrenauer

What is difference? Does anyone know the difference between T-Nex and ETHEPHON 2 SL. Both are made by Quali-Pro. Thanks for the help....


----------



## kdn

PGrenauer said:


> What is difference? Does anyone know the difference between T-Nex and ETHEPHON 2 SL. Both are made by Quali-Pro. Thanks for the help....


Different active ingredients. Both can be used as a PGR, ETHEPHON 2 SL can also be used for seed head suppression.

T-Nex uses *Trinexapac-ethyl 12%*.
ETHEPHON 2 SL uses *Ethephon [(2-chloroethyl)- phosphonic acid] 21.7%*.


----------



## PGrenauer

kdn said:


> PGrenauer said:
> 
> 
> 
> What is difference? Does anyone know the difference between T-Nex and ETHEPHON 2 SL. Both are made by Quali-Pro. Thanks for the help....
> 
> 
> 
> Different active ingredients. Both can be used as a PGR, ETHEPHON 2 SL can also be used for seed head suppression.
> 
> T-Nex uses *Trinexapac-ethyl 12%*.
> ETHEPHON 2 SL uses *Ethephon [(2-chloroethyl)- phosphonic acid] 21.7%*.
Click to expand...

Thanks! Is one better than the other or equally as good?


----------



## Johnl445

Is Is there a reason why people are using Celsius over Fahrenheit when counting GDD for application of PGR? Am I missing something?


----------



## g-man

Easier to calculate. GDD is mean temp - the reference temp. For the cool season PGR the gdd is on 0C. Therefore, mean T - 0 = mean T.

Also, most of the research is done by universities and they use the metric system.


----------



## Johnl445

Ok @g-man I figured there was something to
It.


----------



## drcolossus11

Need a suggestion on my next Tnex app. I have made two applications so far. First was 5ml, second was 10ml and I am not seeing any regulation on my lawn. I have a mix of fescues, king and rye. What would be my next app rate? HOC is 3 inches.


----------



## g-man

At 3hoc, you likely need 20mL or even more. Leave a corner in the backyard untreated so you can see the effect better (aka control plot).


----------



## drcolossus11

g-man said:


> At 3hoc, you likely need 20mL or even more. Leave a corner in the backyard untreated so you can see the effect better (aka control plot).


@g-man 
Thanks! Can I go ahead and throw down another 10ml or should I wait and up it on the next application?


----------



## g-man

At the next.


----------



## drcolossus11

g-man said:


> At the next.


Thanks!


----------



## Ravenallen1971

Two + part question. Does anyone know the ideal temperature range of cool season grasses. Then... does anyone know if you get out of that range does the GDD calculation lose some efficiency? Example we have been in an extended heat wave since mid June (see pictures).


----------



## SNOWBOB11

Most cool season grasses grow best in the 65-75F range for day time highs and mid 50F overnight lows.

The calculation of GDD is based on taking into account temperature. The warmer the avarage the faster it wears off.


----------



## g-man

g-man said:


> For all cool season lawn types at all HOC except greens heights with T-nex in oz/ksqft:


@Huntsw1


----------



## Huntsw1

Thank you @g-man


----------



## Kstawski

How long does it take grass to absorb pgr (T-Nex) with surfactant? If I apply in the early morning and it rains about 24 hours later, would I run into issues?


----------



## SNOWBOB11

You should be good within 4hr after applying. Ideally maybe a bit longer but 24hr is well more than enough time.


----------



## g-man

Don't add surfactant. It already has it.


----------



## Kstawski

g-man said:


> Don't add surfactant. It already has it.


I did not know that! Thanks!


----------



## steffen707

Thinking of doing my first PGR app to my non-reno area. Is that a good or horrible idea with fall nitrogen blitz and wanting to get some spots filled in before winter?


----------



## SNOWBOB11

steffen707 said:


> Thinking of doing my first PGR app to my non-reno area. Is that a good or horrible idea with fall nitrogen blitz and wanting to get some spots filled in before winter?


Not a horrible idea. The grass will be growing faster with the extra nitrogen so nothing wrong with using PGR. On a first app start on the low end of application rate.


----------



## steffen707

SNOWBOB11 said:


> steffen707 said:
> 
> 
> 
> Thinking of doing my first PGR app to my non-reno area. Is that a good or horrible idea with fall nitrogen blitz and wanting to get some spots filled in before winter?
> 
> 
> 
> Not a horrible idea. The grass will be growing faster with the extra nitrogen so nothing wrong with using PGR. On a first app start on the low end of application rate.
Click to expand...

Cool......season PGR application tomorrow. =)

the chart is showing 0.6oz/1000 for residential....when you say the "low end" do you mean use the 0.25oz/1000 golf course fairway amount?

EDIT: I see Tnex uses the same ingredient that was discussed here, "For example, using a PGR with Trinexapac-ethyl 11.3% as the AI, start with 0.3 to 0.4 oz / M (1,000 SF). If that gives you the regulation you desire, stay there. If not, increase it slightly on the next application.", so i'll start with 0.3 to 0.4oz/M


----------



## SNOWBOB11

steffen707 said:


> SNOWBOB11 said:
> 
> 
> 
> 
> 
> steffen707 said:
> 
> 
> 
> Thinking of doing my first PGR app to my non-reno area. Is that a good or horrible idea with fall nitrogen blitz and wanting to get some spots filled in before winter?
> 
> 
> 
> Not a horrible idea. The grass will be growing faster with the extra nitrogen so nothing wrong with using PGR. On a first app start on the low end of application rate.
> 
> Click to expand...
> 
> Cool......season PGR application tomorrow. =)
> 
> the chart is showing 0.6oz/1000 for residential....when you say the "low end" do you mean use the 0.25oz/1000 golf course fairway amount?
> 
> EDIT: I see Tnex uses the same ingredient that was discussed here, "For example, using a PGR with Trinexapac-ethyl 11.3% as the AI, start with 0.3 to 0.4 oz / M (1,000 SF). If that gives you the regulation you desire, stay there. If not, increase it slightly on the next application.", so i'll start with 0.3 to 0.4oz/M
Click to expand...

What's your current mowing hight?

Edit : I just looked at your journal and it looks like your in the 2.5" range? If so 0.3-0.4oz/M is a good starting point.


----------



## steffen707

SNOWBOB11 said:


> steffen707 said:
> 
> 
> 
> 
> 
> SNOWBOB11 said:
> 
> 
> 
> Not a horrible idea. The grass will be growing faster with the extra nitrogen so nothing wrong with using PGR. On a first app start on the low end of application rate.
> 
> 
> 
> Cool......season PGR application tomorrow. =)
> 
> the chart is showing 0.6oz/1000 for residential....when you say the "low end" do you mean use the 0.25oz/1000 golf course fairway amount?
> 
> EDIT: I see Tnex uses the same ingredient that was discussed here, "For example, using a PGR with Trinexapac-ethyl 11.3% as the AI, start with 0.3 to 0.4 oz / M (1,000 SF). If that gives you the regulation you desire, stay there. If not, increase it slightly on the next application.", so i'll start with 0.3 to 0.4oz/M
> 
> 
> 
> Click to expand...
> 
> What's your current mowing hight?
> 
> Edit : I just looked at your journal and it looks like your in the 2.5" range? If so 0.3-0.4oz/M is a good starting point.
Click to expand...

Yeah about 2.5", I've been mowing every two days and slowly dropping 0.25 each Mow cuz I want to get it to around 2", hoping to see the lawn fill in some spots that had little ant hills creep up.


----------



## steffen707

Ahh crap, more questions.

it appears a lot of you spray PGR with chelated iron, which I have. Is this what I should be doing to avoid yellowing?


----------



## cleohioturf

Yes, chelated iron will help avoid bronzing from PGR. I mix ammonium sulfate and ferrous sulfate only because I still have pounds of it sitting around.


----------



## klsmith259

I'm new to applying PGR, understanding it, and tracking it. I currently have KBG SPF-30 in my backyard which I applied PGR to. The dilemma I am having is how to input it to track it. KBG is a cool season grass but SPF30 is a hybrid which holds up to the summer heat. My question is how should I input it to track it? Should it be categorized as 0c or 10c? Does it matter? This past summer it still grew aggressively without any fertilizer. During the cooler months it will grow even faster.

KBG SPF-30
https://www.outsidepride.com/seed/grass-seed/bluegrass-seed/kentucky-bluegrass-hybrid.html


----------



## klsmith259

I think I answered my own question. It still needs to be set as a cool season grass and base temperature. It will still grow in the summer/heat but not as aggressively.


----------



## steffen707

Well my first T-Nex and chelated iron app went without a hitch yesterday. We've been getting rain today so the lawn normally looks great. No yellowing that i've noticed. fingers crossed it works out!


----------



## steffen707

I sprayed 0.3oz/m of T-Nex and 4oz/m of southern ag chelated iron yesterday. not sure how long it takes to make any visual changes, but i don't see any adverse looks. If anything it already is looking more green, but we're also getting a drizzle today.


----------



## schmendog

In a Thirsty Thursday episode @osuturfman mentioned the need to be careful with PGRs and DMIs (makes sense). I'm trying to figure out how long I need to wait after a TNEX app, prior to my first propiconazole app in June?


----------



## VALawnNoob

schmendog said:


> In a Thirsty Thursday episode @osuturfman mentioned the need to be careful with PGRs and DMIs (makes sense). I'm trying to figure out how long I need to wait after a TNEX app, prior to my first propiconazole app in June?


Do you mind summarizing for us what was discussed?


----------



## g-man

schmendog said:


> In a Thirsty Thursday episode @osuturfman mentioned the need to be careful with PGRs and DMIs (makes sense). I'm trying to figure out how long I need to wait after a TNEX app, prior to my first propiconazole app in June?


After gdd 900 from Tnex, it should be ok to use foliar propi.


----------



## g-man

Some info in this blog around PGR and fall applications from Bill Kreuser

https://greenkeeper.blog/2021/09/16/be-careful-with-fall-growth-regulation/


----------



## steffen707

g-man said:


> Some info in this blog around PGR and fall applications from Bill Kreuser
> 
> https://greenkeeper.blog/2021/09/16/be-careful-with-fall-growth-regulation/


Thanks @g-man , to others looking at the GDD and timing PGR applications discussed in this article, look up https://lawntrack.app/ and the thread, https://thelawnforum.com/viewtopic.php?f=4&t=29448
@liamjones created a killer app. I even use it to time my house plant waterings. I might even start putting my furnace filter changes on there. I know it was intended for lawn care, but all these "maintenance type things" I can keep track of there.
DON'T FORGET TO DONATE.


----------



## klsmith259

There is also LittlLEAF - https://www.littlleaf.com. I use both and lean towards LittlLEAF, although it does not have precipitation tracking. It contains prior day actuals the following day which Lawntrack has a 2 day lag. LittlLEAF in my opinion is more visually appealing. They are both great web applications.


----------



## steffen707

klsmith259 said:


> There is also LittlLEAF - https://www.littlleaf.com. I use both and lean towards LittlLEAF, although it does not have precipitation tracking. It contains prior day actuals the following day which Lawntrack has a 2 day lag. LittlLEAF in my opinion is more visually appealing. They are both great web applications.


Is littlLeaf free?


----------



## klsmith259

Yes, it is free. There is a forum post on here from the developer. I'll see if I can't dig it up.


----------



## steffen707

klsmith259 said:


> Yes, it is free. There is a forum post on here from the developer. I'll see if I can't dig it up.


Very cool. The GUI is definately better. Looks like what I was doing on LawnTrack I can still do at LittlLeaf


----------



## Mark B

g-man said:


> Some info in this blog around PGR and fall applications from Bill Kreuser
> 
> https://greenkeeper.blog/2021/09/16/be-careful-with-fall-growth-regulation/


Thanks for posting this, I have been not entirely sure how much PGR to apply after my last one considering dropping fall temps. I was considering stopping already and dealing with any rebound with increased mowing but after reading the article I think I can go half rate now for one last application this season.


----------



## cleohioturf

I would look at your most recent GDD and future weather compared to recent, get an idea on how long you will be to reach your optimal GDD with PGR.

For me, reaching ~250 GDD during the summer is almost every two weeks. By September I can get my last two weeks during the first two weeks but by mid September the outlook puts me closer to 4 weeks to reach ~250 GDD, which then gets close to frost so I back off. I dont want it under regulation by the time we hit first frost, rather have a couple weeks of growth going into the frost and just deal with more mowing.


----------



## Lawn Whisperer

I applied .7oz/M of tnex on 9/24 to regulate the growth while I lower the HOC from 3.25" to under 2" in preparation for overseeding. I wasn't able to get seed down until yesterday, 10/5. Can I apply another application of tnex, maybe a lower rate before germination to extend the regulation? Below is my GDD for 0°C.


----------



## cleohioturf

your grass is still under regulation, is it starting to rebound or are you just asking if applying more will extend your duration? applying during current regulation GDD can cause over regulation, which isnt good.


----------



## Lawn Whisperer

cleohioturf said:


> your grass is still under regulation, is it starting to rebound or are you just asking if applying more will extend your duration? applying during current regulation GDD can cause over regulation, which isnt good.


No rebound yet, just wanted to see if I can get another app before germination and extend the regulation to allow the overseeding to grow. How early can I put the next app? Or do I have to wait until 340 GDD? Or just allow the seeds to germinate and just mow as needed.


----------



## cleohioturf

I wouldnt apply before a day or two to before your total GDD application rate, if you do reapply, use the table to determine best application rate.

did you just broadcast spread or what method did you use for overseeding? What kind of seed did you put down? Without knowing, I would just see what germinates.

In general, I would be weening off PGR for the season anyhow. This is all climate related...you can apply during growth, fall is a great time for growth, but as the growth or clipping yields start to diminish, you need to ease PGR's, which can happen quick. Look at monthly weather and see what you have on the horizon. You might have ability to do a light application and still achieve regulation but remember as weather cools, your GDD lengthens, so a normal two week 255 GDD could turn into 3-4 weeks with cooler days.

Personally I would prefer to not have the grass in regulation going into frost. I like to have nice growth allowing me to cut and control height myself to get to lower fall height with green leaf.


----------



## Lawn Whisperer

I overseeded by slit seeding TTTF and broadcast 5 day pre-germinated KBG.

I wanted to get another application of pgr before the seeds germinated. I don't plan to apply anymore pgr for the rest of the year.


----------



## wiseowl

steffen707 said:


> klsmith259 said:
> 
> 
> 
> There is also LittlLEAF - https://www.littlleaf.com. I use both and lean towards LittlLEAF, although it does not have precipitation tracking. It contains prior day actuals the following day which Lawntrack has a 2 day lag. LittlLEAF in my opinion is more visually appealing. They are both great web applications.
> 
> 
> 
> Is littlLeaf free?
Click to expand...

@klsmith259 I haven't forgotten about you !
ET stuff is on the list, my normal work life got in the way and had to pause some dev work but I'm slowing down for the end of the year and can refocus on the feature list as I'd like to tie ET into the overview page and am going to bring in some enhancements to the GP page.

For @steffen707 if you click on the suggestion under the pgr application I've posted recommended rates for both cool and warm season. Everything is taken care of for you in my app if you aren't already using it.



If you guys have questions or suggestions on the app let me know, I have the support thread in my signature and yes it's free, stable and mobile friendly 

I came in here looking to see what people were doing for PGR  don't mind a warm season guy lurking


----------



## steffen707

wiseowl said:


> steffen707 said:
> 
> 
> 
> 
> 
> klsmith259 said:
> 
> 
> 
> There is also LittlLEAF - https://www.littlleaf.com. I use both and lean towards LittlLEAF, although it does not have precipitation tracking. It contains prior day actuals the following day which Lawntrack has a 2 day lag. LittlLEAF in my opinion is more visually appealing. They are both great web applications.
> 
> 
> 
> Is littlLeaf free?
> 
> Click to expand...
> 
> @klsmith259 I haven't forgotten about you !
> ET stuff is on the list, my normal work life got in the way and had to pause some dev work but I'm slowing down for the end of the year and can refocus on the feature list as I'd like to tie ET into the overview page and am going to bring in some enhancements to the GP page.
> 
> For @steffen707 if you click on the suggestion under the pgr application I've posted recommended rates for both cool and warm season. Everything is taken care of for you in my app if you aren't already using it.
> 
> 
> 
> If you guys have questions or suggestions on the app let me know, I have the support thread in my signature and yes it's free, stable and mobile friendly
> 
> I came in here looking to see what people were doing for PGR  don't mind a warm season guy lurking
Click to expand...

Thanks @wiseowl


----------



## VALawnNoob

I know it is probably too early for PGR but I have been on my 3rd mow already and starting to see the beginning of Spring flush. If I'm going away for a week due to kid's spring break, is it too cold right now to apply PGR? I just want to make sure the lawn doesn't grow too fast for the 1 week break in spring time and get away from me.


----------



## drcolossus11

Can anyone point me to the information on re-entry for QualiPro T-Nex? I read through the label a few times now and am not seeing it.

Thanks!


----------



## drcolossus11

drcolossus11 said:


> Can anyone point me to the information on re-entry for QualiPro T-Nex? I read through the label a few times now and am not seeing it.
> 
> Thanks!


I found it. No Re-entry without shoes until the grass has dried.


----------



## confused_boner

Just bumped up from .125 to .250 per M....looking gooooood


----------



## CDR

My front is very thick and lush while the back could use a bit more help to thicken. The front was sod though and back was seed. 
I've read a lot between various places and hear mixed things.

Would starting PGR apps in the back help with thickening by pushing lateral growth by limiting top growth?

Thanks


----------



## shifco

g-man said:


> schmendog said:
> 
> 
> 
> In a Thirsty Thursday episode @osuturfman mentioned the need to be careful with PGRs and DMIs (makes sense). I'm trying to figure out how long I need to wait after a TNEX app, prior to my first propiconazole app in June?
> 
> 
> 
> After gdd 900 from Tnex, it should be ok to use foliar propi.
Click to expand...

Hey G-man,

If I need to use propiconazole with my PGR apps this summer, is it best to just dial down the PGR rate to avoid overregulation?? The 900 gdd is quite a bit.

Also, is azoxystrobin subject to the same thinking??


----------



## g-man

Do you really *need* to use propi? There are other fungicides. Any DMI will cause issues with PGR. Greenkeeperapp has a way to predict the combined effect if you still want to use it. I stopped using propi.


----------



## Bean4Me

How can I tell if my PGR is expired? I purchased a jug of it July 2020. I keep it in the garage during the season and bring it in over the winter to avoid freezing. I sprayed a few days ago and it doesn't appear to be regulating. Grass is growing like crazy. I'm tempted to do a second application this weekend to see if it was a fluke.


----------



## SNOWBOB11

Bean4Me said:


> How can I tell if my PGR is expired? I purchased a jug of it July 2020. I keep it in the garage during the season and bring it in over the winter to avoid freezing. I sprayed a few days ago and it doesn't appear to be regulating. Grass is growing like crazy. I'm tempted to do a second application this weekend to see if it was a fluke.


Shouldn't be bad if it's less than 2 years old. My bottle of t-nex is 5 years old and still works fine. What's your hight of cut and what rate did you use?


----------



## Bean4Me

1.25" about 0.5oz


----------



## SNOWBOB11

That is more than high enough dose for regulation. Maybe just the spring flush keeping grass growing.


----------



## Bean4Me

I know... so after applying a few days ago then mowing last night it was like my grass wasn't even regulated. I might do another app this weekend because with all the rain we've been getting its only gonna get worse.


----------



## VALawnNoob

If it is the first application of the season it takes a bit to get going from my experience. Spring flush is going strong so I would see how the 2nd application respond first.


----------



## SnootchieBootchies

I've used T-Nex in the past without issue, but always during high growth times. Had a poa A issue last year and did prodiamine fall app and while it, so far, looks to be a lot less, I'm thinking of PGR app to impede seed head development. Problem is my KBG is slower to wake up this year due to less rain and probably too low N program in the fall. Any risk of applying PGR with about a 50/50 mix of dormant/wakening KBG?


----------



## steffen707

Does PGR help KBG spread, or does it just assist in root development, by suppressing leaf growth?


----------



## Lawnbadix

How could it possibly do the second thing without later on going over for the first point you asked for? For me it's just logical.


----------



## steffen707

Lawnbadix said:


> How could it possibly do the second thing without later on going over for the first point you asked for? For me it's just logical.


Rhyzomes would be a lateral growth. 
Root development would be a downward growth.

I don't have a doctorate in KBG, so I'm asking the question, "To assume makes an *** out of U and Me". 😉


----------



## bernstem

steffen707 said:


> Does PGR help KBG spread, or does it just assist in root development, by suppressing leaf growth?


I have not seen any good data that PGR increases root depth or spreading by any significant amount. The marketing would suggest it and lots of bloggers will say it, but I don't know that the data is there. Maybe I have just not found it yet.


----------



## Lawnbadix

I don't have a comparison to how it would look without me using PGR but I have planted in july, this is from march. I've never seen such deep roots on my location before when digging.
It's not even 1 year old lawn. For me it seems to work.



I'd guess these rocks and close to pure compressed loam hindering even deeper root dev below the humus.



The white stuff in the hole is Perlite btw, I basically put some better stones below. Atleast they store some water.


----------



## steffen707

Lawnbadix said:


> I don't have a comparison to how it would look without me using PGR but I have planted in july, this is from march. I've never seen such deep roots on my location before when digging.
> It's not even 1 year old lawn. For me it seems to work.
> 
> 
> 
> I'd guess these rocks and close to pure compressed loam hindering even deeper root dev below the humus.
> 
> 
> 
> The white stuff in the hole is Perlite btw, I basically put some better stones below. Atleast they store some water.


Thanks for sharing. I did pgr once last year, very interesting. Now that i'm going to push mow my lawn, i'll definately want to reduce the amount of mowing required.


----------



## drcolossus11

I applied .5oz of T-Nex to my lawn (kbg, TTTF and prg) on 5/5. I have accumulated 173 GDD so far, but I am starting to see some rebounding in some areas. Last cut was on 5/11 at 2" HOC. This morning when I went out I had a few patches that were over 10in. Overall I had to raise my HOC to 3.5 for this mow to not break the 1/3 rule.

Should I wait the full 300 GDD before reapplying?


----------



## Want2BS8ed

g-man said:


> Do you really *need* to use propi? There are other fungicides. Any DMI will cause issues with PGR. Greenkeeperapp has a way to predict the combined effect if you still want to use it. I stopped using propi.


FWIW, I've had some lengthy discussions with Bill Kreuser on Greenkeeperapp's DMI models and currently they only have models setup for bentgrass greens (and allegedly fairways). Plans are to work on models for bluegrass, ryegrass and bermudagrass throughout the summer though.

Until then, the utility for DMI/PGR stacking predictions in Greenskeeper will be somewhat limited. Even more so if your running a TTTF rough.


----------



## steffen707

g-man said:


> Do you really *need* to use propi? There are other fungicides. Any DMI will cause issues with PGR. Greenkeeperapp has a way to predict the combined effect if you still want to use it. I stopped using propi.


What is the issue with propi? 
What other fungicides do you use instead?


----------



## VALawnNoob

Propi is a DMI fungicide as g-man mentioned. It will cause issues with PGR and over-regulate.


----------



## Lawnbadix

Overregulation means yellowing right? Or does it just safe $$$ if properly abused?


----------



## TheZMan

Greenkeeper - is there a free option or is it monthly and yearly rates?


----------



## Bean4Me

drcolossus11 said:


> I applied .5oz of T-Nex to my lawn (kbg, TTTF and prg) on 5/5. I have accumulated 173 GDD so far, but I am starting to see some rebounding in some areas. Last cut was on 5/11 at 2" HOC. This morning when I went out I had a few patches that were over 10in. Overall I had to raise my HOC to 3.5 for this mow to not break the 1/3 rule.
> 
> Should I wait the full 300 GDD before reapplying?


I don't know how many GDD I span but if I see things start to rebound I reapply as needed. I noticed my early application this year didn't take as well so I'll probably respray this weekend just to keep it regulated. I also apply at a rate of 0.5oz on my lawn.


----------



## steffen707

VALawnNoob said:


> Propi is a DMI fungicide as g-man mentioned. It will cause issues with PGR and over-regulate.


oh, so the DMI type fungicide combined with PGR over-regulates, but there are other non-DMI fungicides that won't do that?


----------



## Lawnbadix

Sorry for asking but when talking about 0.5 oz, is that like 14-15 mL? I use some converter to make things easier for most of you so to share I'd like to find the corresponding proper conversion within my app.
Also that's the rate we talk about as per 1000 square feet afair?
Thanks.


----------



## Want2BS8ed

TheZMan said:


> Greenkeeper - is there a free option or is it monthly and yearly rates?


They did away with their free option and the monthly cost is substantially more than the annual.

I'd signed up before the new slate of free options had really ramped up. My renewal is coming-up and I'm on the fence, in large part because their DMI models don't cover TTTF and/or roughs. That gets weighed against their other predictive models (seed head reduction, dollar spot, etc.) and inventory functions.

There is a pretty substantial discount for being a homeowner (but you have to ask) and they have been exceptionally responsive in responding to questions and bug fixes.


----------



## steffen707

TheZMan said:


> Greenkeeper - is there a free option or is it monthly and yearly rates?


support the forum, @liamjones created a badass program called Lawn Track, checkout the thread here
https://thelawnforum.com/viewtopic.php?f=4&t=29448 :thumbup:


----------



## steffen707

Lawnbadix said:


> Sorry for asking but when talking about 0.5 oz, is that like 14-15 mL?


Google knows everything.


----------



## Lawnbadix

I'm not familiar with this stuff, thanks for sharing. I keep it in mind.

I only use far below .2 oz and don't have heavy growth. I mow once a week just to do it. My lawn is fed and was well growing before I started. Now it's main growing season here but it grows maybe 2 mm a day or less. Hard to tell as I'm getting lazy with mowing ofc.
Using a mix of Prohex, Trin and Paclo rotation always with 2 AI same time, trying to differ atleast 1 AI any application. I haven't gotten any rebound effect. Gonna keep my 2/3/4 weeks schedule.
It's amazing results for the tiny use. Got ***/Poa Supine turf stand <1 year old maybe that's why.


----------



## drcolossus11

Bean4Me said:


> drcolossus11 said:
> 
> 
> 
> I applied .5oz of T-Nex to my lawn (kbg, TTTF and prg) on 5/5. I have accumulated 173 GDD so far, but I am starting to see some rebounding in some areas. Last cut was on 5/11 at 2" HOC. This morning when I went out I had a few patches that were over 10in. Overall I had to raise my HOC to 3.5 for this mow to not break the 1/3 rule.
> 
> Should I wait the full 300 GDD before reapplying?
> 
> 
> 
> I don't know how many GDD I span but if I see things start to rebound I reapply as needed. I noticed my early application this year didn't take as well so I'll probably respray this weekend just to keep it regulated. I also apply at a rate of 0.5oz on my lawn.
Click to expand...

Thanks! Trying not to over regulate like I did last season. The FF in my front yard did not fair so well when I did…


----------



## LegionLawn

TheZMan said:


> Greenkeeper - is there a free option or is it monthly and yearly rates?


https://www.littlleaf.com/

Found it on the forum.


----------



## FuzzeWuzze

Lawnbadix said:


> Overregulation means yellowing right? Or does it just safe $$$ if properly abused?


I made this mistake on my Mazama, it turned a weird grey green color, not yellow.


----------



## Green

Hey all,
Anyone using anything other than Trinexapac or Anuew? I'm using Trinexapac on selected area(s) this Spring as usual. It looks like these are pretty much the only 2 PGRs approved for residential lawn use. For example, Paclo is not (even though it's been around a long time, which is odd). Are any others approved in the US? Anuew is pretty new, and got approved for residential quickly. There seems to be no pattern for what goes and doesn't. Now, maybe someday Paclo will, but it might take another decade or two, which is useless.


----------



## Lawnbadix

Using KBG/Supine BG
prohexadione calcium
Paclo
Trine
Ethephon


----------



## TheZMan

LegionLawn said:


> TheZMan said:
> 
> 
> 
> Greenkeeper - is there a free option or is it monthly and yearly rates?
> 
> 
> 
> https://www.littlleaf.com/
> 
> Found it on the forum.
Click to expand...

Thank you


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## Grizzly Adam

I am having trouble finding the exact info I need. I have seedlings that are about 2-3 weeks old. What effect will t-nex have on them? Also, my bluegrass is spreading some and helping fill in some damaged areas-- will t-nex help, hinder or have no effect this process?


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## confused_boner

Grizzly Adam said:


> I am having trouble finding the exact info I need. I have seedlings that are about 2-3 weeks old. What effect will t-nex have on them? Also, my bluegrass is spreading some and helping fill in some damaged areas-- will t-nex help, hinder or have no effect this process?


I personally would not use PGR on new seedlings until the next growing season. The normal advice is to apply PGR right BEFORE seeding to suppress existing grass growth, which allows the seedling to grow past the existing canopy to become established. Applying PGR to new grass would be counteractive to this...

You can certainly start applying low rates of PGR in the next growing season to the new grass once it's semi-established. This MAY promote lateral growth per the TNEX label but it's very minor. You will mostly see clipping suppression.


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## steffen707

Grizzly Adam said:


> I am having trouble finding the exact info I need. I have seedlings that are about 2-3 weeks old. What effect will t-nex have on them? Also, my bluegrass is spreading some and helping fill in some damaged areas-- will t-nex help, hinder or have no effect this process?


I too want to know the answer to your second question.


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## SNOWBOB11

It will slow the growth of the new seeds at a time you want them to be growing.

T-nex doesn't really help with spreading bluegrass in my experience. Nor does it hinder.


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## Lawnbadix

When overseeding or seeding bigger bare spots, for me what it does is slowing down the top growth which I don't care about but neither do mind. I focus on what happens with the new seed. My <1 year established grass will be kept cut around 1.5 inches. Over weeks, I have no more bare spots because it doesn't put top growth, it just somewhat slides on the ground. What might sound counterproductive to many worked out great for me. During autumn and winter I don't spray. During that time when it grows, it'll just fill what's left and during spring, it'll explode with rhizomes. It's hard for weeds to find any place to sprout. I barely use any weed killer at all on my 10 month old young lawn but where I started seeding outside my test areas, the weeds exploded because there is simply dirt with no real competition.

Spraying fresh seed with PGR, makes my branches exploding. It's a real world experience. Not anything you get advised.
I do anything I can different to learn and have a talk about that here in tlf.
It's dark outside here but imagine some heavy ball of fine ryegrass. This is my KBG looking like when hit with it so young.


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## Lawnbadix

Put seed on almost pure moss and PGR'ed it.


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## Want2BS8ed

Quick question/poll on using PGR's season long.

In a high heat/humidity transition zone where growth plunges in July & August, do you:

A) Continue applying the same amount of PGR (same volume of AI),
B) Reduce the amount of PGR applied (less AI), or
C) Stop applying PGR's all together until temperatures cool?

Let's assume the lawn is irrigated and never goes fully dormant and application intervals increase as GDDs tighten.


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## VALawnNoob

Want2BS8ed said:


> Quick question/poll on using PGR's season long.
> 
> In a high heat/humidity transition zone where growth plunges in July & August, do you:
> 
> A) Continue applying the same amount of PGR (same volume of AI),
> B) Reduce the amount of PGR applied (less AI), or
> C) Stop applying PGR's all together until temperatures cool?
> 
> Let's assume the lawn is irrigated and never goes fully dormant and application intervals increase as GDDs tighten.


Good question as I've been wondering the same thing. Last year I stopped appying PGR all together as temp went up in July in VA. There was also risk of fungus so propiconazole as a DMI fungicide was not possible with PGR.


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## Want2BS8ed

Thanks @VALawnNoob. Currently using Anuew and Headway G, so DMI's definitely factor in to the overall decision.

Appreciate your responding, because I am genuinely interested in how others approach suppression when growth slows in the summer.


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## steffen707

Lawnbadix said:


> Put seed on almost pure moss and PGR'ed it.


What's the main point of your findings? It looks like the moss died, is that what you're trying to emphasize?


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## bernstem

@VALawnNoob @Want2BS8ed PGR in summer heat depends on how you manage the grass. Assuming you are managing for maximum performance you won't be letting the grass get stressed and will be watering to maintain quality, then I would continue at the same or, at most, 50% of the spring rate. You gain some heat stress benefits from using PGR and you don't want the rebound growth of just stopping.

If you are watering to prevent dormancy and letting the grass stress, then you may want to stop the PGR.

The other aspect is the use of DMI fungicides. Those you generally want to hold during the summer. That timing also works well for resistance management rotation.


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## Want2BS8ed

Thanks @bernstem. That makes a lot of sense.

Clearly I'm going to need to rethink my fungicide rotations (Thiophanate-Methyl, Azoxystrobin, and
Propiconazole) because the Headway G in July & August is looking less and less viable.

Thanks again for reply, it's very helpful.


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## Lawnbadix

steffen707 said:


> What's the main point of your findings? It looks like the moss died, is that what you're trying to emphasize?


See the dwarfish KBG? I used bit seed only. It outcompetes the moss. I'll post some pictures later how it looks now.


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## steffen707

Lawnbadix said:


> steffen707 said:
> 
> 
> 
> What's the main point of your findings? It looks like the moss died, is that what you're trying to emphasize?
> 
> 
> 
> See the dwarfish KBG? I used bit seed only. It outcompetes the moss. I'll post some pictures later how it looks now.
Click to expand...

Cool, thanks.


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## steffen707

i sprayed pgr once last year.
This weekend i'm going to try 0.4oz/m tnex and 4oz/m southern ag chelated iron.

I've read that the 4oz/m chelated iron is supposed to be watered in, but the tnex is foliar and supposed to allow to dry 4 hrs before water.

So how long do YOU GUYS, wait to water the lawn after tnex+iron?


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## SNOWBOB11

Watering it into the root zone would be if your ph is below 7. Above and you need to apply foliar and let sit.


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## steffen707

SNOWBOB11 said:


> Watering it into the root zone would be if your ph is below 7. Above and you need to apply foliar and let sit.


I'm at 7.2, so i'll let it sit.

Anybody use cytogro with tnex?


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## Want2BS8ed

I'm spraying Anuew with Lesco 12-0-0 Iron w/ Zinc & Micros + a NIS. Unless the label says otherwise, I would wait at least 4 hours before rain or watering.


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## Lawnbadix

steffen707 said:


> Cool, thanks.


It was somewhere on that picture, mainly moss previously, *** filled in and outcompeted all the things. Now it's fresh sanded and cut on lowest possible setting (hence yellowing). Will see how it goes.


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## cokenner

Read the thread and couldn't find an answer.

Could I START applying PGR in this summer heat? 
I have been using it on my Bermuda for the past few weeks with great success, but have been undecided in whether or not I want to use it in my KBG in the summer heat.

I'm getting some heat stress in spots of my lawn and new top growth is lime green.

Should i just carry on through the summer without or can I apply PGR for the first time and get some benefit?


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## confused_boner

cokenner said:


> Read the thread and couldn't find an answer.
> 
> Could I START applying PGR in this summer heat?
> I have been using it on my Bermuda for the past few weeks with great success, but have been undecided in whether or not I want to use it in my KBG in the summer heat.
> 
> I'm getting some heat stress in spots of my lawn and new top growth is lime green.
> 
> Should i just carry on through the summer without or can I apply PGR for the first time and get some benefit?


If you are taking about TNEX, the label suggests to apply before the onset of stress.


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## cokenner

confused_boner said:


> cokenner said:
> 
> 
> 
> Read the thread and couldn't find an answer.
> 
> Could I START applying PGR in this summer heat?
> I have been using it on my Bermuda for the past few weeks with great success, but have been undecided in whether or not I want to use it in my KBG in the summer heat.
> 
> I'm getting some heat stress in spots of my lawn and new top growth is lime green.
> 
> Should i just carry on through the summer without or can I apply PGR for the first time and get some benefit?
> 
> 
> 
> If you are taking about TNEX, the label suggests to apply before the onset of stress.
Click to expand...

Yessir, thank you.


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## bernstem

cokenner said:


> confused_boner said:
> 
> 
> 
> 
> 
> cokenner said:
> 
> 
> 
> Read the thread and couldn't find an answer.
> 
> Could I START applying PGR in this summer heat?
> I have been using it on my Bermuda for the past few weeks with great success, but have been undecided in whether or not I want to use it in my KBG in the summer heat.
> 
> I'm getting some heat stress in spots of my lawn and new top growth is lime green.
> 
> Should i just carry on through the summer without or can I apply PGR for the first time and get some benefit?
> 
> 
> 
> If you are taking about TNEX, the label suggests to apply before the onset of stress.
> 
> Click to expand...
> 
> Yessir, thank you.
Click to expand...

You can start applying PGR in the heat. Start off at low rates and increase as the lawn tolerates it. I generally back off a bit on my dosage in the summer heat. Growth potential is already decreased so you can really put the brakes on growth with PGR when it is 90+ degrees.


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## nwlawnguy

I'm in Vancouver, WA with RTF I have been mowing at 1.5 inches since I started reel mowing and while I love mowing every couple of days with our raining weather sometimes it stretches to 4 or 5 days so I decided to try the Primo Maxx PGR and man does it work, After about 5 days I got maybe a half catcher off my total yard front and back. It's not big only about 2300 square feet but still only a slight amount after 5 days is something.


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## Want2BS8ed

Curious, what is your threshold for rain?

Sitting at 35% suppression and falling and GreenKeeper is saying today is the day to reapply (my original estimate was for tomorrow so everything is on track). Need at least a 4-hour window per label to be rainfast. DarkSky, Wunderground and the 8 global models available through PredictWind all agree; it's going to rain almost everyday for the next _15 days_. Chance and timing are all over the place.

I can and have cut in the rain, put down granular and sprayed ground apps. A 15% to 20% chance of rain is about my threshold for sneaking in a foliar app.

What's yours?


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## Goater90

I am wondering about the effects PGR has on roots and if it can worsen an already bad thatch problem. I recently took some core samples for the first time and found I have about 2 inches of thatch/root layer. Pretty ugly. I read everywhere that PGR promotes root growth, but would it drive the roots down into my soil layer and help my turf health, or would it just increase root production and add to the thatch layer I've just started trying to battle? Thanks for any input.


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## steffen707

Goater90 said:


> I am wondering about the effects PGR has on roots and if it can worsen an already bad thatch problem. I recently took some core samples for the first time and found I have about 2 inches of thatch/root layer. Pretty ugly. I read everywhere that PGR promotes root growth, but would it drive the roots down into my soil layer and help my turf health, or would it just increase root production and add to the thatch layer I've just started trying to battle? Thanks for any input.


Holy cow! That thatch layer is taller than some of my roots!

I too am curious if PGR is suspected to increase thatch production, or does it drive roots down? It doesn't seem to do anything to my plugs to spread them laterally, with T-Nex anyway.


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## Cluelessone

I've been too chicken to reapply PGR in the summer heat. Last year when I did, between that and the army worms I ended up losing a tremendous amount of my lawn. Maybe I'll sneak a light application in, as I'm mowing about every 5-6 days and would like to push that to 7+ if I can.

At the very least, I should put some down where the gutter emitters are, as that area isn't stressed as bad due to all the water it gets.


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## Want2BS8ed

Interesting blog post from GreenKeeper that touches on cool season turf, PGR's and HOC...

https://greenkeeper.blog/2022/08/17/late-summer-sugar-lows/

It's been a brutal and inconsistent summer. This is the first full season of using a PGR. While I'm not overly happy with how things are looking, relative to my neighbors, things are looking pretty decent.


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## steffen707

Yeah I'm working on best of street, then neighborhood, then town. Mine is looking pretty darn good in comparison.


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