# Ok, that was unexpected (no lime needed, P and K literally off the chart)



## sirwired (May 21, 2020)

Recently got my soil test back from NC Dept. of Ag. This, errr... was not what I expected at all. (I have 2 mo-old Zoysia sod, and I sampled down to about 4"... I suppose the top 1" or so is soil from the sod farm and the compost that the landscaper laid down underneath it.)

pH is in the low-6 range in my clay soil, despite the fact that I've never specifically added lime, ever, as long as I've lived here (14 years now.) Does TruGreen typically include Lime as part of their regular service, and I just wasn't really aware?

P and K are literally off the scale: With an optimum range listed of 50 to 70, front has P 154 and K 113. My backyard has P of 258 and K of 145. (NC Agronomics does not report on N, due to it being unstable in the soil; they assume you need it at a steady clip, and give recommendations accordingly.) So their recommendations are N-only ferts, at 1lb N, twice a year.

Other stats (just picking the back lawn here):
HM 0.56%, W/V 0.85, CEC 12.7, Mn-I 425, Zn-I 544, Cu-I 170, S-I 149.

Their lime suggestion is 0lb across the board, and N-only fertilizer (not surprising.)

Did I somehow royally screw up my sampling process, or did TruGreen simply saturate my lawn with gobs of P and K? The state agronomic lab isn't exactly a fly-by-night operation (Dr. Mehlich of Mehlich-3 fame actually developed his tests while working there), so I'm having trouble imagining an across-the-board mistake on their end.

Here's my back lawn as an example:


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## Deadlawn (Sep 8, 2020)

Ironically, you have zoysia which will pretty much grow in anything, but here you are with the perfect soil probably helped to some extent because of that compost layer. I had an area of zoysia when I lived in NJ. It never needed anything. Although in NJ, it was only green from May to Oct., but during the growing season, it grew and I still had to mow it. And it was thick enough that the mower would labor.

I have a word for you - lucky! Can I trade some of your soil for my sterile sandy soil? ;-)


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## jtuber (Sep 15, 2020)

Lime increases soil ph so I am confused by your post.


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## Deadlawn (Sep 8, 2020)

jtuber said:


> Lime increases soil ph so I am confused by your post.


I was thinking this too. pH above 6 is high enough and not worth liming. Most of our trees in the east actually like slightly acidic soils and could be negatively impacted if the pH is too high.


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## bernstem (Jan 16, 2018)

I wouldn't work to increase the pH, 6.2 is just fine. The high P and K are almost certainly from the layer of compost which is typically very high in both nutrients. The good news is you only need Nitrogen. 5 lbs/year may be high for Zoysia, but check with the warm season forum.


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## sirwired (May 21, 2020)

I realize I don't need to add lime; I'm just baffled my soil *isn't* acidic, because it's never been limed to my knowledge in the 13 years I've lived here. I thought Carolina clay naturally became acidic over time.

And the 5lb/yr wasn't for 5#N/k, it was for 5#/k of 21-0-0.


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## bernstem (Jan 16, 2018)

Tru-Green will often lime in the fall. Depending on the program it may be included or an extra cost.


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## Deadlawn (Sep 8, 2020)

sirwired said:


> I thought Carolina clay naturally became acidic over time.


That all depends on the plants and trees you have. Oak leaves and conifer needles are acidic. Maples and birches are acidic, but less so. Other tree leaves are neutral or slightly alkaline,

The other issue is acid rain which affects the Northeast more so than the mid-Atlantic or Southeast. When I lived in NJ, I had a soil test and the pH came in at 6.5. Now that I'm in MA, my pH is 5.5.


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## 01Bullitt (Aug 31, 2020)

Deadlawn said:


> sirwired said:
> 
> 
> > I thought Carolina clay naturally became acidic over time.
> ...


Carolina clay is definitely acidic. This was a soil test I had done in 2018.


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## Deadlawn (Sep 8, 2020)

01Bullitt said:


> Deadlawn said:
> 
> 
> > sirwired said:
> ...


4.9pH? Whoa! That would be great for my blueberry shrubs!


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