# Propiconazole Mixed with TNex



## Dlux4life (Oct 10, 2020)

Hoping this is not a doomsday thread. I applied TNex at the label rate of .75 oz per 1k sq ft and Propiconazole 14.3 at 1 oz per 1k sq ft this morning without understanding Propi's growth suppression effects. I have a mix of 80% kbg and 20% prg. Had anyone on here experienced this before? Any suggestions on what can be done or what I may be expecting on the coming days / weeks?


----------



## JerseyGreens (Aug 30, 2019)

What are your temps the next few days? Honestly that is a very high dose of PGR for a KBG/PRG lawn...good thing you didn't have a higher dose of Propi.

It's going to start looking over regulated and crappy as early as tomorrow. Will take some time for it to recover but nothing doomsday...you probably didn't kill your lawn.

Was this your first time using PGR?


----------



## SNOWBOB11 (Aug 31, 2017)

What is your current cutting hight?


----------



## Dlux4life (Oct 10, 2020)

This was the 3rd time applying the t-nex this season. I'm about 45 min north of Boston. I'm looking at 90 tomorrow and then a stretch of mid 70's the next 5 days. Rain off and on.

The .75 oz per 1k sq ft was the label rate on the tnex brochure for a kbg/ prg mix. Is it normal to put down lesser applications of it?

My current hoc is .7".

What do you mean by over regulated looking?

I'll take some pictures every few days to post as a reference.


----------



## Pete1313 (May 3, 2017)

It's going to look bad for a few weeks. Even at 1 oz/M of propi. Good news is it is grass and will recover.


----------



## JerseyGreens (Aug 30, 2019)

Dlux4life said:


> This was the 3rd time applying the t-nex this season. I'm about 45 min north of Boston. I'm looking at 90 tomorrow and then a stretch of mid 70's the next 5 days. Rain off and on.
> 
> The .75 oz per 1k sq ft was the label rate on the tnex brochure for a kbg/ prg mix. Is it normal to put down lesser applications of it?
> 
> ...




On my last awesome sauce application (T-nex+FEature+citric acid+N) I mistakenly did an extra east to west spray in that red circled area...followed by my normal north to south sprays. That got a double dose of the sauce at 0.33oz T-nex per K...

It's recovering now but looked brown, beat up, diseased for 2 weeks now...that's what your lawn will probably look like for a bit.


----------



## SNOWBOB11 (Aug 31, 2017)

At a higher HOC it might look less bad but at .70" you'll notice it. As Pete said it will recover.


----------



## bernstem (Jan 16, 2018)

Be aware that T-nex and Propi over regulation looks a lot like disease. At that dose and combination with higher temps, you might see some browning.


----------



## g-man (Jun 15, 2017)

As a reference, most of us at 3/4in hoc use 0.3 to 0.4oz/Ksqft of tnex.


----------



## Dlux4life (Oct 10, 2020)

Thanks for all the help and input everyone. And thanks g-man for the tnex rate recommendation.


----------



## Dlux4life (Oct 10, 2020)

JerseyGreens said:


> Dlux4life said:
> 
> 
> > This was the 3rd time applying the t-nex this season. I'm about 45 min north of Boston. I'm looking at 90 tomorrow and then a stretch of mid 70's the next 5 days. Rain off and on.
> ...


Thanks for the photo! Needless to say your lawn still looks great. Here's to a quick recovery (and a lesson learned for me!)


----------



## NJ-lawn (Jun 25, 2018)

I have a 100% KBG lawn and I use .75/1M with no problems but I mow @3/4".


----------



## JerseyGreens (Aug 30, 2019)

NJ-lawn said:


> I have a 100% KBG lawn and I use .75/1M with no problems but I mow @3/4".


Damn, that is a high dose for a low cut KBG. 
Do you only have to mow once a week?


----------



## NJ-lawn (Jun 25, 2018)

JerseyGreens said:


> NJ-lawn said:
> 
> 
> > I have a 100% KBG lawn and I use .75/1M with no problems but I mow @3/4".
> ...


Yeah pretty much but no issues, today I noticed what might be beginning of dollar spot. I been using .75 oz/1M all season. This is the 2nd full season since my reno and I noticed it's filling in nicely. Zero bare spots.

With all this humidity and flooding rains I think it's starting to catch up with me. Prob time for a chemical app


----------



## Dlux4life (Oct 10, 2020)

So here it is today. Things are still looking alright.


----------



## Huntsw1 (Jun 3, 2021)

g-man said:


> As a reference, most of us at 3/4in hoc use 0.3 to 0.4oz/Ksqft of tnex.


I am really struggling to understand GDD and the time between tnex and prop applications? I have TTTF at 4 inches in Indianapolis. Can i just go by every 3 weeks or so at 0.3 oz of tnex and 1 oz of prop during the summer?


----------



## g-man (Jun 15, 2017)

GDD is growing degree days. For cool season lawns using Celsius, you just add the mean temperature for that day since the day you last applied it. In summer, it would be like adding 21, then 20, 25, etc. Once you reach ~300, that's when you re apply and start counting from zero.

Why use gdd? Warmer days makes the product in the plant reduce faster than colder days. In the peak of summer you can be applying every 12 days, vs 22 days in the fall. You will get better results using GDD.

I have a google sheet that i shared that will track it for you. But Liam made a website that would be easier to setup.

I strongly advise not to apply foliar propi to a lawn that is under tnex regulation. The effect of propi over regulates and makes it look ugly.

For your 4in hoc in Indy, you likely need 0.75oz to 1oz/Ksqft of tnex instead of 0.3oz. the longer leaves means it needs more product in the plant. Think of it like Tylenol dosage for kids vs adult. More body mass = higher dosage. Next time you spray (if the rain stops), leave a square section in the backyard un treated so you can see the regulation effect.


----------



## JerseyGreens (Aug 30, 2019)

g-man said:


> GDD is growing degree days. For cool season lawns using Celsius, you just add the mean temperature for that day since the day you last applied it. In summer, it would be like adding 21, then 20, 25, etc. Once you reach ~300, that's when you re apply and start counting from zero.
> 
> Why use gdd? Warmer days makes the product in the plant reduce faster and colder. In the peak of summer you can be applying every 12 days, vs 22 in the fall. You will get better results using GDD.
> 
> ...


Great explanation! This one post should be stickied in the PGR/cool season thread to perfectly summarize GDD/PGR/application amounts. That thread can become a bit overwhelming for beginners venturing into PGR.


----------



## Dlux4life (Oct 10, 2020)

All the rain has been helping. Nothing major that I am seeing so far. It has been about 4-5 days since the treatment.


----------



## Huntsw1 (Jun 3, 2021)

g-man said:


> GDD is growing degree days. For cool season lawns using Celsius, you just add the mean temperature for that day since the day you last applied it. In summer, it would be like adding 21, then 20, 25, etc. Once you reach ~300, that's when you re apply and start counting from zero.
> 
> Why use gdd? Warmer days makes the product in the plant reduce faster than colder days. In the peak of summer you can be applying every 12 days, vs 22 days in the fall. You will get better results using GDD.
> 
> ...


Thank you so much for the detailed explanation. How many applications before I start seeing results? I am still mowing every 4 days or so even though we haven't had rain in a long time and I am manually watering.


----------



## shadowlawnjutsu (Jun 9, 2020)

Just a follow up question. How long after applying propi, in my case 2oz/KSqft, should I wait before I can apply TNex?


----------



## g-man (Jun 15, 2017)

~ 5weeks if you want no interaction.


----------



## shadowlawnjutsu (Jun 9, 2020)

g-man said:


> ~ 5weeks if you want no interaction.


Thanks @g-man! I might use cleary or other type 3 fungicide next time as an alternative to propi.


----------



## Lawn Whisperer (Feb 15, 2021)

shadowlawnjutsu said:


> g-man said:
> 
> 
> > ~ 5weeks if you want no interaction.
> ...


It applies to all DMI fungicides (propiconazole, myclobutanil, etc). 
Saw this post by @bgrass on warm season, it also applies to cool season lawns. https://thelawnforum.com/viewtopic.php?p=273198#p273198


----------

