Have soil tested, by a lab that gives organic recommendations, to learn the total and available levels of organic matter, nitrogen, calcium, magnesium, sulfur, phosphate, potassium, sodium, chloride, boron, iron, manganese, copper and zinc. Tissue sample tests are important to see what nutrients are being taken up by the plants. Check for life by counting the earthworms in a square foot of soil - should be at least ten.
Q. For soil testing why do you and Bob W recommend the Texas Plant and Soil Lab in Edinburg Tx and do not recommend the Texas A&M Soil Lab? J. W. Lindale, TX
A. No testing lab is perfect but A&M’s is our least favorite because of two main reasons. First and very important, they don’t even include organic matter, carbon or humus in their tests and reports. That’s the most important thing to know about soils. Secondly, their test uses a harsh acid that breaks the soil down and allows them to identify the chemical components but gives no information as to what nutrients are available to the plants. TP&SL recommends too much fertilizer in some cases and is way to in love with sulfur but their test uses a carbon dioxide extraction process which mimics how things work in the soil. Their tests are hugely more accurate about what nutrients are available to the plants.