# On the Fence.. need advice



## Scagfreedom48z+ (Oct 6, 2018)

So my backyard PH is slightly low(6.2) and my umass soil test recommends doing 75 lbs of lime. I was planning on putting down 35 lbs now and another 30 in the fall to get to that threshold.

My other situation is that my sulfur and calcium levels are really low in both my front and back turf. My plan would be to add the sta green gypsum to work in those numbers

My dilemma is, in regards to the back yard where the PH is slightly low, should I just add the lime and skip the gypsum or should I add both? I'm just concerned it's going to be too much calcium and other elements all added at once. Is there one either the gypsum or lime that would be recommended to add as a priority over the other?


----------



## Ridgerunner (May 16, 2017)

Without seeing the soil test, we're working blind. Generally, I wouldn't suggest using gypsum as a sulfate/sulfur source. After N, sulfate is one of the most transient nutrients. You do not want to keep adding Ca on a regular basis to keep replenishing S. Better to combine N and S sources for regular applications. Use ammonium sulfate and kill both birds with one stone. Potassium sulfate (SOP) would be an additional option. Any low Ca (or Mg) levels are very likely to be corrected by the lime. pH 6.2 isn't a particularly low pH and is one where many will leave it alone. 75 lbs/M of lime seems a little high for correcting Mass. soil at that pH. Measure twice and cut once.


----------



## Scagfreedom48z+ (Oct 6, 2018)

Ridgerunner said:


> Without seeing the soil test, we're working blind. Generally, I wouldn't suggest using gypsum as a sulfate/sulfur source. After N, sulfate is one of the most transient nutrients. You do not want to keep adding Ca on a regular basis to keep replenishing S. Better to combine N and S sources for regular applications. Use ammonium sulfate and kill both birds with one stone. Potassium sulfate (SOP) would be an additional option. Any low Ca (or Mg) levels are very likely to be corrected by the lime. pH 6.2 isn't a particularly low pH and is one where many will leave it alone. 75 lbs/M of lime seems a little high for correcting Mass. soil at that pH. Measure twice and cut once.






I've also been dropping 2 lbs of SOP and TSP throughout the growing months last year(2lbs per 1M) and I'm also going to be sticking to the same regiment with that this year as well. I also put down 2 lb of each per 1M of each for April.


----------



## Ridgerunner (May 16, 2017)

Other than P and K, it's not that bad. You'll get the most bang for your buck in turf performance by addressing them. Can you buy P fertilizers in Mass? Also see if you can source SOP 0-0-50 locally at a reasonable price, then get back with what you find and we'll look at options.


----------



## Scagfreedom48z+ (Oct 6, 2018)

Ridgerunner said:


> Other than P and K, it's not that bad. You'll get the most bang for your buck in turf performance by addressing them. Can you buy P fertilizers in Mass? Also see if you can source SOP 0-0-50 locally at a reasonable price, then get back with what you find and we'll look at options.


Thanks for the advice. Yes I've been able to source TSP and SOP reasonably in Mass for the last year or so. I've been applying 2lb of each April-Oct of 2020 and have already applied 2lb of each for April of 2021


----------



## Lawn Whisperer (Feb 15, 2021)

Scagfreedom48z+ said:


> I've been applying 2lb of each April-Oct of 2020 and have already applied 2lb of each for April of 2021


The math doesn't add up here. You've applied 14lbs/1k sq. ft. of TSP and SOP each; you're p and k should be well above optimum, in excess actually. 
When was this sample taken? And how does this soil test compare to you previous soil test? Sampling method? I would assume that you're not bagging clips.


----------



## Ridgerunner (May 16, 2017)

Interesting. At those application rates (even though MMorgan results are a fraction of what other methods report) I would have expected more of a change in P and K. I found your 2079 test. Did you post your 2020?
Regardless, unless it's a sampling error keep applying the TSP and SOP as you have been.
although I wouldn't expect for you to see any change in turf performance, you can raise Ca levels if that's your desire. For the 6.6 pH soil, gypsum is the right tool 20-25 lbs/M should add about 150-200 ppm without changing pH. Keep in mind, adding Ca will tend to remove Mg and interfere with K reserves as they all compete for cation sites on the soil.
For the 6.2 pH, if you want to maintain pH, use gypsum, If you want to raise it, you ccould use dolomitic lime to raise both Ca and Mg. K issues with lime are the same as with gypsum.
It looks like @g-man and @bernstem advised you previosly. Maybe the have some more insight from past interaction.


----------



## Scagfreedom48z+ (Oct 6, 2018)

Lawn Whisperer said:


> Scagfreedom48z+ said:
> 
> 
> > I've been applying 2lb of each April-Oct of 2020 and have already applied 2lb of each for April of 2021
> ...


Well I have to say but your guess is as good as mine! LOL. I hope this opens up a little discussion because I too thought my P&K would have been corrected by now I only bag clippings at the beginning of spring to collect the POA A seeds and once we get into late June/Early July, I don't bag. Here are the products I've been applying for the last year at 2 lbs per 1M every month during the growing season of April to Oct. Also below is the soil test from 2020. I also would apply these granular products after mowing, never before, in fear of sucking them up with the mower. I know it's common sense but putting it out there.


----------



## Ridgerunner (May 16, 2017)

It's just a guess, but it's possible that the P is binding with all of the Ca you've been applying (gypsum and lime) and that might explain why your Ca levels haven't gone up much too. K; however is still unexplained. Have you considered testing using Mehlich 3 testing?


----------



## Scagfreedom48z+ (Oct 6, 2018)

Ridgerunner said:


> It's just a guess, but it's possible that the P is binding with all of the Ca you've been applying (gypsum and lime) and that might explain why your Ca levels haven't gone up much too. K; however is still unexplained. Have you considered testing using Mehlich 3 testing?


This is pretty interesting. I've never heard of that test before. Is it more detailed that what I'm getting now?

I'm curious on what I would need to do to unbind the P and I'm stump with the K myself. I thought this years 2021 soil test would have shown better outcomes. I've also applied foliar 0-0-29 during the hotter months to help with stress from turf grass pro. Yeah, I'm pretty confused...


----------



## g-man (Jun 15, 2017)

How much did you apply of what in 2020?


----------



## Scagfreedom48z+ (Oct 6, 2018)

g-man said:


> How much did you apply of what in 2020?


According to my log of 2020: excluding the usual foliar apps of N, micros, foliar 0-0-29, feature, etc

4/7 applied lime: 
240 lbs over 11M
400 lbs over 16M

8/16 applied gypsum 
200 lbs over 11M
300 lbs over 16M

14 lbs total of SOP and TSP - 2 lbs per month for 7 months

These are pretty much the only granular apps I do now since I've gotten used to the foliar apps now.

I also suffered excessive die off/thatch more than ever this year. It's the first spring that I've had to deal with it this bad, especially since I did an earlier than usual,successful overseed in early fall 2020/late summer.
I'm not sure if it was because of an aggressive fall N blitz or I had lingering P&K that never took by the soil. It was to the point that I had to detach 2x's this spring which was something that I was fighting but had no choice. The lawn looked like crap. It's certainly looking better after dethatching but not as good as I hoped.


----------



## g-man (Jun 15, 2017)

The 14lb is per 1000sqft, correct? So 420lb for your 30k?


----------



## Scagfreedom48z+ (Oct 6, 2018)

g-man said:


> The 14lb is per 1000sqft, correct? So 420lb for your 30k?


Yes exactly of TSP and SOP. Same amount per
Month for each.


----------



## Lawn Whisperer (Feb 15, 2021)

60 lbs of TSP every month for 7 months (8.4 of 50lb bags) and 60 lbs of SOP every month for 7 months spread (8.4 bags of 50lb bags) over 30,000 square feet (not metric).

Please excuse me if I seem to be sarcastic, but I'm just trying to figure out where all you p&k are going.


----------



## Scagfreedom48z+ (Oct 6, 2018)

Lawn Whisperer said:


> 60 lbs of TSP every month for 7 months (8.4 of 50lb bags) and 60 lbs of SOP every month for 7 months spread (8.4 bags of 50lb bags) over 30,000 square feet (not metric).
> 
> Please excuse me if I seem to be sarcastic, but I'm just trying to figure out where all you p&k are going.


I'm with ya! Unless they screwed up the soil test but what are the chances of that? I've already at stocked up on both TSP and SOP
for the next few months. I don't know how there hasn't been a much bigger jump for
Both for this years soil test.


----------



## g-man (Jun 15, 2017)

Something is very odd. It is like there was no change outside of the pH. You K even dropped a bit


----------



## Lawn Whisperer (Feb 15, 2021)

Your situation still has me baffled. Do you mind describing your soil physical conditions? Soil type (sandy clay), soil layers, watering schedule, compaction, water absorption, aeration, slopes, flooding, etc...
Are you sampling between 3-4 in? Maybe a sample of all the layers might give you a better reading.


----------



## Scagfreedom48z+ (Oct 6, 2018)

Lawn Whisperer said:


> Your situation still has me baffled. Do you mind describing your soil physical conditions? Soil type (sandy clay), soil layers, watering schedule, compaction, water absorption, aeration, slopes, flooding, etc...
> Are you sampling between 3-4 in? Maybe a sample of all the layers might give you a better reading.


So my soil type given that I'm in Massachusetts is more clay with gravel 4-6 below the soil.

The water schedule- I have irrigation and inirrigate 3 days a week, only once in the early am(2am start) with a 45min watering cycle per each zone during the heat of the summer

Water absorption and compaction - this has gotten better the last couple of years. It's been a marathon over the last 3 years but with the amendments(humic, fulvic, etc) and working on the PH and adding gypsum has seemed to help with this. I used to get pooling water in low spots a few years ago but that doesn't seem to be an issue any longer.

The soil sampling can piggy back off this as well. Seemed like my soil samples were deeper than years past(4-6 inch) sample plugs. I've tried to get deeper/longer plugs but I eventually hit the gravel and can't go any further.

I've also email umass since they have my last 3 years worth of samples on record to see if they can offer any insight to this as well.


----------



## Sphero43 (Jul 23, 2020)

Scagfreedom48z+ said:


> Ridgerunner said:
> 
> 
> > Other than P and K, it's not that bad. You'll get the most bang for your buck in turf performance by addressing them. Can you buy P fertilizers in Mass? Also see if you can source SOP 0-0-50 locally at a reasonable price, then get back with what you find and we'll look at options.
> ...


Where in MA were you able to source SOP?


----------



## Lawn Whisperer (Feb 15, 2021)

All that p&k has to be somewhere, either it's leaching out of your topsoil into the gravel or it's created a layer on the upper topsoil. Maybe consider sampling all layers of your soil 0-4" or 0-6" and just removing thatch and roots. Additionally, a Mehlich 3, which I believe UMass provides get you another perspective of p&k levels.
Also, I remember you posting regarding having a thick turf and thatch layers. Watering too often can create heavy thatch. My goal is to water once a week at 1"-11/2" to promote deeper roots. Your situation, 6" of soil and weather might differ.

In the mean time, it might be best to hold off on the TSP and SOP applications or just spoon feed a 4-1-2 ratio as you apply nitrogen.

Good luck on solving the mystery of the missing P&K.


----------

