# Soil results - low PH, high K



## CLT49er (Jun 19, 2020)

Soil results just came. Here are their recommendations. Seems like standard kaolinite clay soil in the Charlotte area. Soil sample results last year were about the exact same.

PH 5.3 - apply 57lbs per 1k
-Will split that up in two apps. February and May. 
-Last year I was at a 5. I applied the recommend 69lb/1k. But did it all at once. Heavy! 😬. Ph only raised .3?

Phosphorus is low
-Recommends 3lbs per 1k spring and again summer 
-Might do a third 3lbs application. 
-Probably didnt correct it enough last year.

Potassium is excessive. 
-any concerns here?
-will try to apply no K all year.

Micros seem ok
-will use micros during PGR apps

CEC low
-Carbon ProG seems like a good value. Will go heavy if budget allows.


----------



## Ridgerunner (May 16, 2017)

Clemson?
If so, I believe they use M1 to extract nutrients.
To convert to ppm, divide lbs/acre by 2.
Potassium levels of 125 ppm are not an issue.
Phosphorous at 8 ppm is low.
You can find links to the M1 (Mehlich 1) sufficiency level ranges, formulas and 8 step calculation process for adjusting nutrient reserves and maintenance application amounts You can use the guide and links here and Mehlich 1

BTW, changes in pH from lime applications can take 1 to 2 years on a loam soil. On a clay soil, even a weathered low CEC clay, it will take ven longer for the change to work down to depth.


----------



## CLT49er (Jun 19, 2020)

Thanks. Yes. That was Clemson. They make it easy to submit and turnaround is great.

On the PH. Since I went so heavy last year and met what they suggested, should I continue to add lime or wait until I see those numbers rise next year or so?


----------



## Ridgerunner (May 16, 2017)

There are a couple of calculators out there for approximating residual lime credit.
A very rough method is to credit a prior lime application at an 8%/month depreciation rate.

From NCDA:

"The current pH is the pH of the sample analyzed. Since some lime applied within the past 12 months may not have fully reacted, "residual credit" (RC) is given to applied lime, depending on the soil class and how recently it was applied. Residual credit is reduced by 8 percent per month from the time of application to the time of soil sampling for mineral soils and by 16 percent per month for mineral-organic and organic soils."

For example, A soil report recommends the application of 40lbs/M of lime, but you already applied 50lbs/M of lime 7 months ago:
7 X 8%= 56%
50 lbs of lime X 56% = 28 lbs of lime sitting un-activated
40 lbs of lime - 28 lbs = 12lbs of lime to be applied.

Remember that most of that 69 lbs that activated that you applied last year has only been able to affect the top 1" or so of soil raising that layer pH close to a pH of 8. It's going to take a long time for it to work down to the 3-4" depth.


----------



## CLT49er (Jun 19, 2020)

Whoa. Thanks so much @Ridgerunner !


----------



## Ridgerunner (May 16, 2017)

@CLT49er 
That's wrong. I need to slow down. It should be:
For example, A soil report recommends the application of 40lbs/M of lime, but you already applied 50lbs/M of lime 7 months ago:
7 X 8%= 56%
50 lbs of lime X 56% = *28 lbs of lime activated, 22 lbs of lime un-activated
40 lbs of lime - 22 lbs = 18lbs of lime to be applied.*
Sorry about my haste.


----------



## CLT49er (Jun 19, 2020)

Lol. Close enough and understood the logic. Thanks!


----------

