Question
QUESTION: After reading your blogs, I had a soil test done last October in our new house. I was not sure what I was going to do with it when I got it but it seemed like a good idea to get the report anyway. What I got was a long list of information, Most of it is too technical for me to understand.  For now, I would like to understand the line about "Cation Exchange Capacity". What would be a good number and what would cause it to go bad?  What would you do to correct it if there is a problem? Thanks in advance.
ANSWER: Values for Cation Exchange Capacity --  "CEC" -- measure the ability of a soil sample to hold nutrients.  The larger the CEC, the more ability to store Calcium, Potassium, Magnesium and other nutrients.  Clay soil tends to have high CEC values, as high as 25 milliequivalents per 100 cu. cm -- which is very desirable.  Sandy soil is the opposite, usually between 1 and 3 milliequivalents per 100 cu. cm.).  Organic amendments will fix both, correcting the tilth of the Clay and the low CEC numbers for the Sand.

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QUESTION: The test says my pH is "very high" and recommends a system to correct it. What would you say to do? And how would I know if this is an "organic" change to the pH or not?

Answer
You can lower the pH of your soil many ways.

Alkaline soil is common in arid climates -- rain is not leaching Calcium out of the soil.  This restricts the availability of some very basic nutrients.  Grass growing in soil with a pH above 7.8 is always going to be deficient in Iron, Zinc and Phosphorus.

But there's no quick fix.  Because of the Limestone in the soil, it is very difficult to lower the pH.  Sulfur is a non-Organic solution.  Compost, aged Manure, Humus, Peat Moss and other Organic matter will lower the pH and support microbes.  I don't recommend wood or bark because they tie up Nitrogen, which is murder on grass.

Amending your soil will also improve the soil structure.  Grass loves a good tilth.

Thanks for writing.