# Adding Limestone to soil ph 6.4



## Mr Strauss (6 mo ago)

First off, hello everyone.

I've found a dangerously addicting :shock: hobby...

I had a soil test done this year by my local university extension.

It came back as having a ph of 6.4. It suggests I add 70lbs of Limestone per 1,000sqft of yard. Now, that would be about 1,000lbs of limestone for my yard(around 15,000sqft)

According to my Googling, a ph of 6.4 is 'normal'.

Was there a mistake in the suggestion to add that much lime? Does this seem right to you all? It seems like dumping a half a ton of limestone on my yard would, ummm, create unwanted results.

If it matters, Phosphorus came back at 29ppm and Potassium is at 149ppm.

All are classified as 'Below optimum'

If it's right, I'll do it, but it just seems like a colossal amount of lime to put down.


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## g-man (Jun 15, 2017)

Welcome to TLF.

Can you post the actual test results? I would not touch a pH of 6.4.


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## Mr Strauss (6 mo ago)

Sure thing.


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## g-man (Jun 15, 2017)

It seems that they are basing their recommendations on the acidity reading. I think they are assuming that the pH will go down over time. My suggestion is to not do lime this year. Next year test again and see if it needs adjustment.

Phosphorus is borderline deficient, so you can apply some.


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## Pannellde (7 mo ago)

Could just be a boilerplate comment. At 6.4 I wouldn't apply lime or you'll end up in the 7(s) ≈ no bueno. I am at 5.4 and will buy a ton of lime this fall to get me to 6.4.


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## Mr Strauss (6 mo ago)

I see.

It didn't sit right with me to lay down 1,000lbs of lime when my ph was in normal range.

So, from this soil test, the only thing you would do is add phosphorus?


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## g-man (Jun 15, 2017)

And nitrogen.


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## hawkman248 (6 mo ago)

The "correct" pH is dependent on soil type and crop. Some crops (blueberries, for example) may require a more acidic soil (lower pH) while some more basic (higher pH) than "normal". On coastal plain soils in VA, a 6.2 is often considered adequate. No matter the crop, when you are at your target pH (6.4), there's no reason to add lime yet. (Adding compost or nitrogen fertilizer can lower pH a bit but I doubt you're adding a lot. Remember the test could even be off by one or two points in either direction!

Just sample next year and see what happens. I assume you took a composite sample (cores of soil from multiple locations, mixed together as one sample)?

Unless my math fails me, 70 lbs/1000 ft^2 works out to 1.5 tons of lime per acre. That's a LOT of lime. Many farmers aren't putting out that much lime at all. If so, it's usually because they got behind or are in an organic soil situation (read: former swamp, a peat soil) where pH is always dropping fast.


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## pennstater2005 (Jul 17, 2017)

That's funny cause I just got my PSU test back and my pH was near identical recommending adding lime at same rate as yours. I'm not planning on doing anything.

They do have you adding a little P and K.


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## robjak (Mar 31, 2020)

https://agsci.psu.edu/aasl/soil-testing/fertility/handbooks/turf/tables/lime-recommendations-turf

https://agsci.psu.edu/aasl/soil-testing/fertility/handbooks/turf/recommendations/2001-home-lawn-maintain


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## Ridgerunner (May 16, 2017)

I believe there is an issue with PENN's recommendations;
If you're willing to do the math:
https://www.ncagr.gov/agronomi/buffacid.htm


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