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Jericho Vermont

My test results came back with a pH reading of 6.2 and a buffer pH reading of 6.8. I have never had a pH reading so low and was wondering if anyone knew the difference between the two. Sounds like I may need a bunch of lime this yr. Thanks for the help. John

9/19/2006 8:57:47 AM

Picton,ON (j.vincent@xplornet.ca)

I heard a real good description of this. Think of your soil as a cup full of vinegar. The PH is a measure of the acidity of the vinegar in the cup. The Buffer Ph is a measure of how much vinegar is in the cup. The difference being, regardless of how much vinegar is in the cup, the PH is the same. The amount of vinegar determines how much base you need to neutralize it.
A lime recommendation, based on a buffer PH is far more accurate than one made on PH alone. A soil with a Buffer PH of 6.8 requires far less lime to adjust than a soil with a buffer PH of 6.2. If your target PH is 6.5, with a buffer PH of 6.8, you require about 42 lbs/ 1000 ft2 of lime. Of course this varies with lime quality.

9/19/2006 1:42:24 PM

Jericho Vermont

Thanks John. That makes sense. I am not used to getting such an updated soil sample done. They also suggested to use Dolomite to raise my pH. I believe I should use a little less poundage with this. Thanks again. john

9/19/2006 8:16:59 PM

Picton,ON (j.vincent@xplornet.ca)

The reason they are recommending dolomitic lime is likely because you need magnesium. If you can get it, it is your best choice. As far a neutralizing ability, it dosn't matter whether it is dolomitic or calcitic lime

9/19/2006 9:09:22 PM

Ctpumpkin@optonline.net

6.2 isn't very low. When I bought this place the soil was pH 5.6!!! It require nearly 300 lbs of lime per 1000 over 3 years to get the pH to 6.8!

The buffer pH is where you will arrive if you follow the labs recommendation for lime.

9/19/2006 11:49:27 PM