# Soil Test - Low in P and K. Is it too late to add K in VA?



## VALawnNoob (Jun 9, 2020)

As part of fall overseeding, I put down Lesco Starter Fert: 14-20-4. This may help my P levels as noted by the Soil Test below. However, I'm wondering if I should also put down Lesco SOP 0-0-50 - especially in the back yard? It is 9/30 and @g-man recommends to others not to put down K due to snow mold in Oct/Nov. Should I just wait until spring time to spread the K or am I still in the window (northern VA)?

Front Yard:

Rear Yard:


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## ken-n-nancy (Jul 25, 2017)

VALawnNoob said:


> ... I'm wondering if I should also put down Lesco SOP 0-0-50 - especially in the back yard? It is 9/30 and @g-man recommends to others not to put down K due to snow mold in Oct/Nov. Should I just wait until spring time to spread the K or am I still in the window (northern VA)?


There is an increased risk of snow mold with increased potassium levels, particularly with late season applications of potassium.

However, snow mold typically doesn't occur without at least 30 days of continuous snow cover. Unless you at altitude in the mountains, I would think the likelihood of snow mold in Virginia would be close to zero, even with fall applications of potassium.

You know your local climate; if you haven't had 30+ days of continuous snow cover in the past, I would have no reservations with applying potassium throughout the fall.


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## VALawnNoob (Jun 9, 2020)

We have had snow apocalypse 10 years ago where that happened but I guess It is very unlikely. 
How is my CEC? Is it low, medium or high? I gave clay soil so honestly thought I should have higher CEC?


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## Virginiagal (Apr 24, 2017)

Your CEC is low, especially the 4.2. Best to do more frequent fertilizer at lower rates. Instead of doing 1 lb/1000 sq ft of a nutrient once a month, do 1/2 lb twice a month.


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## g-man (Jun 15, 2017)

Your P is very low. It is actually deficient. You should continue applying P while the grass is still growing.


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## VALawnNoob (Jun 9, 2020)

g-man said:


> Your P is very low. It is actually deficient. You should continue applying P while the grass is still growing.


@g-man After the test, I have put down 14-20-4 as part of overseeding. I only have a bag of CarbonX, 2 bags of GreenTRX and 1.5 bags of Milo left in the garage - neither of which has that much P. Do you know if K4L 6-6-6 can be mixed in for foliar absorption? Their rate of 1-4 tsp per gallon app rate doesn't sound like much. 
Is it better to wait until Spring or should I go out and buy more starter fert to put down now to get the deficiency corrected?


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## g-man (Jun 15, 2017)

I would buy a fert with P to apply to the soil. MAP, DAP, TSP or a starter fertilizer.


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## VALawnNoob (Jun 9, 2020)

Can someone please check my math here to see if I understood Waypoint's recommendation?

Using backyard guidelines:

The Waypoint rec says to put down 2 lbs of P. My 50lb bag of 14-20-4 has label that covers 10k sq ft. I would have 10 lbs of P in that bag and each backyard (10k) application would put down 1 lb of P per 1k. That means if I put down 2 separate application of the starter fert then I would have met their recommendations?

My 0-0-50 has label that covers 25,000. If I apply that SOP I would put down 1lb of K per 1k and I would need 3 applications?


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## Deadlawn (Sep 8, 2020)

VALawnNoob said:


> Can someone please check my math here to see if I understood Waypoint's recommendation?
> 
> Using backyard guidelines:
> 
> ...


2lbs/1000sqft of P seems excessive for one application. Waypoint probably means you need that total amount, not all at once. I would follow bag rates and follow up with another spring app.


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## Virginiagal (Apr 24, 2017)

20 lb of SOP will deliver 10 lb of K over 10,000 sq. ft, so 1 lb per 1000 sq ft, which is a normal application. To get 3 lb per 1000 sq ft, you would do three separate applications, so you would need 60 lb of SOP and you'd do 20 lb over 10,000 sq ft each time. In general don't apply more than one lb of a nutrient per 1000 sq ft in a single application. For the P, do one lb now, another lb in the spring and you will have met the 2 lb recommendation. The soil tests give recommendations for a year.


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