Game plan after soil test results.

Dave81NJ

LawnSite Member
Alright ... let's get very granular here. (Cool Season Lawn). After having my soil test done, I sent it to the infamous John Perry who gave some great advice and it was the best $15 spent (https://shop.lawncology.com/collections/frontpage/products/lawncology-soil-test-reading)
He noted that due to some issue with CEC numbers, he suggested that I work on the soil and try to spoon feed the lawn every 3-4 weeks, instead of bigger dozes of Nitrogen every 1.5 or so months. Plus, stick to 3lb of N and 0.5lb of P and K per year. His feedback on my soil test here (https://www.youtube.com/watch?v=R-M_mq3DBpg). Hope John doesn't mind me sharing.
Based on his feedback .... questions that hopefully you guys here can address.
  1. John suggested Calcitic Lime (Yes, may raise Ph which doesn't need help, but it is needed to increase the Calcium levels for me). I found a few, but not sure which product is the best for me.
  2. https://www.lowes.com/pd/Soil-Docto...rganic-Gypsum-Improves-Soil-Structure/3062445
  3. https://www.lowes.com/pd/Sta-Green-Fast-Acting-Lime-25-lb-Organic-Lime-Ph-Balancer/1001424982
  4. https://www.lowes.com/pd/Sta-Green-30-lb-Organic-Lime-PH-Balancer/50189499
  5. I’ve started applying my special mix of Humic Acid + Kelp + Supertrhive monthly. Now, Kelp supposedly has Nitrogen 1-2%, phos 0.23%, potash 6% … is it OK to apply it even though he suggests going very light on P and K and should these NPKs be added up to the usual granular season applications I do?
  6. John suggested not to apply Potassium this year, but Winterizer fert has a ton of it. Don't use?
  7. Since I seeded the lawn 3 weeks ago, my last fert app was a starter and thus, high level of Phosphorus. Plan was to add some again in 3 weeks (smaller rate) with a bit of Milorganite before soil is too cold for it and then finish up with Synthetic fert like Winterizer Fert. ... thus pushing more Nitrogen before winter.
So far in 2020, below is what I've applied;
0.7 N, .93P, 0.23k
0.55 N, 0P, 0.11K
0.8 N, .53P, 0K
0.8 N, .53P, 0K
Total= 2.85N, 1.99P, 0.34K
Thanks.

P.S. Another thing I am taking into consideration now ... about 60% of my lawn is at some form of a slope and that angle, though not crazy, is noticeable when it comes to water running off. Because of this, I changed my watering schedule to do 2 scheduled watering, splitting up total time into 2 (6 zones system). Just like watering, I assume same effect can be had with fertilizing where some part of that fertilizer will run off? So breaking up season fertilizing into spoon feeding of let's say 0.3lb of N every 3-4 weeks instead of 0.8lb 3-4 times a year may make more sense?

soil test.jpg
 

Attachments

  • soil test.jpg
    soil test.jpg
    316.7 KB · Views: 66

RigglePLC

LawnSite Fanatic
Location
Grand Rapids MI
I am not a soil scientist. I had to hit "control-plus" to enlarge the soil test to see it better.
I think you are using too much phosphorus--that would be unlawful in some states and near Chesapeake Bay--probably not needed. Causes algal blooms in water.
Sandy soil? Did you apply potassium recently? Potassium is high--however it is water soluble--and considering your low CEC, would be lost quickly during a heavy rain or sprinkling. I suggest a small amount with every treatment to reduce leaching loss, and keep the grass steadily supplied with K. You need about one-seventh as much K as compared to nitrogen.

Calcitic lime is OK, (your calcium is slightly low) --but don't go nuts with it. Mildly acid soil is fine for grass--however an alkaline pH would make iron unavailable. You don't want iron chlorosis.

Yes, you have to add the small amounts of mineral nutrients added with the special booster supplements, as part of your yearly program. You therefore need slightly less of your annual NPK.
It is probably difficult to increase your CEC (cation exchange capacity). You need more organic matter--dark color in your soil, less sand, more clay and loam. Probably best to add some compost or two organic ferts per year--Milorganite or chicken pellets for instance. Sandy soil will remain sandy soil for the most part.

I would not use a high potassium (K), soil if it were contained in a winter fertilizer. Too water soluble--easily lost because sandy soil with low CEC will not hang onto it. A true premium fertilizer will have a high ratio of slow release nitrogen. Look for 30--better yet--50 percent slow-release nitrogen. This does not leach and feeds the grass slow and steady--almost as if you had a fertile organic soil.

Correct! You do not want run-off from the slope in your yard. Two short water applications are better than than one long soaking.
 
Last edited:
OP
D

Dave81NJ

LawnSite Member
I am not a soil scientist. I had to hit "control-plus" to enlarge the soil test to see it better.
I think you are using too much phosphorus--that would be unlawful in some states and near Chesapeake Bay--probably not needed. Causes algal blooms in water.
Sandy soil? Did you apply potassium recently? Potassium is high--however it is water soluble--and considering your low CEC, would be lost quickly during a heavy rain or sprinkling. I suggest a small amount with every treatment to reduce leaching loss, and keep the grass steadily supplied with K. You need about one-seventh as much K as compared to nitrogen.

Calcitic lime is OK, (your calcium is slightly low) --but don't go nuts with it. Mildly acid soil is fine for grass--however an alkaline pH would make iron unavailable. You don't want iron chlorosis.

Yes, you have to add the small amounts of mineral nutrients added with the special booster supplements, as part of your yearly program. You therefore need slightly less of your annual NPK.
It is probably difficult to increase your CEC (cation exchange capacity). You need more organic matter--dark color in your soil, less sand, more clay and loam. Probably best to add some compost or two organic ferts per year--Milorganite or chicken pellets for instance. Sandy soil will remain sandy soil for the most part.

I would not use a high potassium (K), soil if it were contained in a winter fertilizer. Too water soluble--easily lost because sandy soil with low CEC will not hang onto it. A true premium fertilizer will have a high ratio of slow release nitrogen. Look for 30--better yet--50 percent slow-release nitrogen. This does not leach and feeds the grass slow and steady--almost as if you had a fertile organic soil.

Correct! You do not want run-off from the slope in your yard. Two short water applications are better than than one long soaking.

Thank you so much. I've been now studying available to me fertilizers. For the past 3 years used mostly Milorganite and now began to utilize Pure Organic fertilizer (Pure Organic 10-0-2 25lb) at rate of 0.4N it will also provide 0.08K) at suggested application it will net 0.50 of N, 0.00 of P, 0.10 of K.

My knowledge in fertilizers is minimal and other than NPK, not sure what else to consider. Below is a list of fertilizers I've looked at and now am trying to see how to utilize. Plan is to feed soil 9 times and braking that up into;
total of fert 9 apps, every 4 weeks with the following Nitrogen per 1,000.
.65, .4, .3, .3, .3, .3, .3, .5, .5

Fertilizers;
Milorganite 6-4-0 32lb (.4N = 60lb. = 0.27P) $16 = $30/app
0.77 of N, 0.51 of P, 0.00 of K

Pure Organic 10-0-2 25lb (.4N = 36lb. = 0.08K) $23 = $33/app
0.50 of N, 0.00 of P, 0.10 of K

Sta Green Reg 29-0-5 42lb (.4N = 13lb. = 0.07K) $34 = $10/app
0.81 of N, 0.00 of P, 0.14lb of K

The Andersons 25-0-3 50lb (.4N = 15lb. = 0.05K) $32 = $9/app
0.96 of N, 0.00 of P, 0.12 of K

CX DIY 24-0-4 45Lb (.4N = 15lb. = 0.07K) $60 = $20/app
0.72 of N, 0.00 of P, 0.12 of K

Sta-Green Winterizer 32-0-10 13.5lb
0.86 of N, 0.00 of P, 0.27 of K

So 2-3 servings of Milorganite and starter fertilizer in fall will provide enough of Phosphor and use of Pure Organic will provide enough of Potassium. Use of synthetic quick release fert in the late fall would provide a good green up in spring?
 

Top Forums



Top