Agriculture Reference
In-Depth Information
Readily available soil testing kits are entirely sufficient for
the home gardener's needs.
When you gather soil for a soil test, clear the top inch of soil
away and then gather your sample. Do this in several places,
collecting a heaping tablespoon from each location. Mix them
all together in a jar. I happen to use raised bed gardening, so I
test each bed, gathering my sample from several places within
each bed. If you are using a tilled plot, just gather from
several sites in the plot if the soil is reasonably uniform. If the
soil is obviously variable within the plot, test the different
areas separately.
Each soil test has its own instructions which will vary with
manufacturer, so I'll leave you to perform the tests. As the
tests rely on comparing the color of a solution to the color of
a chart, the one piece of advice I would give is to view the
tests in the shade on a sunny day as that will give the most
true color comparison. If you can't do that, fluorescent
lighting is your next best bet. I put a sheet of white paper
behind my solution and color comparison chart to aid in
interpreting the colors.
Interpreting Soil Test Results
Except for pH, the results of home soil tests are not given in
absolute numbers. Instead, they are reported broadly as
“depleted”, “deficient”, “adequate”, or “sufficient”. If the test
indicates sufficient levels of a nutrient, then nothing need be
added, but if the test indicates anything less than sufficiency
you'll need to supplement the soil.
