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.
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.