Soil Testing for Homeowners

Should I have my soil tested? 

A soil test done by a commercial laboratory like A and L Soil Testing Laboratory in Modesto, California, costs from $60-$75. It’s important that a soil test is submitted to a soil testing laboratory that uses appropriate testing. In other words, if you live in the desert don’t send it to a soil testing laboratory that’s in a wet climate.

Sample Soil Test Report for Fruit Trees in the Desert

Soil tests are mostly about what fertilizers and soil amendments should be applied to get a desired yield. I was in in the former Soviet Union years ago when a member of Parliament once asked me, “What is the maximum wheat yield in the United States?” I told him, “US farmers don’t maximize yields. They maximize profits.” Soil tests help farmers “maximize their profits".

Soil Chemistry

Soil tests are primarily aimed at a “soil’s chemistry” to aid a famers profitability. Soil tests will not tell you why a plant died, or chemicals added to the soil that killed a plant. An agricultural soil test won’t tell you that. Those tests can be done, however, but are much more expensive and requires a consultant to guide you.

How Often?

What good are soil tests to a homeowner and when should they be done? A serious gardener should submit a soil sample as soon as new property or growing area is purchased. A “first time” soil test establishes a “baseline” and tells you at the beginning what’s adequate about your soil chemistry and what’s missing. After that a soil test is submitted by homeowners about every four or five years to make sure “they are on track” with their fertilizer and soil amendment applications.

This is a soil test done by a homeowner. Garbage in, garbage out. I learned a long time ago to be careful sending soil samples in for analysis or doing it yourself. Luckily, this soil test matches what a desert soil sample report might look like.

Soil Samples or Sample?

Soil tests are a smaller sample of a larger soil sample taken from the top of the soil to the depth plant roots grow. Several smaller samples representing this depth are added together. A very clean five-gallon bucket is used for mixing the larger soil sample so that a smaller sample, a pound or so, can be submitted for testing. Expect results in about a week after they received your sample. If you’re having trouble interpreting them, hire a consultant the first time so that you are taught how to read them.