Agriculture Reference
In-Depth Information
Inexpensive soil tests are available to test the pH, nitrogen,
phosphorus, and potassium content of soil. A couple of weeks
after the soil in the bed has been prepared and compost and/or
manure have been worked in, you should test the soil's
nutrient content and amend it properly. The most important
factor in the long-range viability of your soil is organic matter
provided by compost and manures, so always make sure that
there is plenty of organic matter first, and then test to see
what kind of fertilization is needed.
You can buy a soil test kit at most garden centers, and most
give results for each nutrient as being depleted, deficient,
adequate, or sufficient. The latter two descriptions can be
confusing because in ordinary English, they have identical
meaning. For the purposes of interpreting soil tests, consider
“adequate” to mean that there is enough of the measured
nutrient for plants to survive but not necessarily thrive. If the
soil test indicates the amount to be “sufficient,” then there is
enough of the nutrient to support optimal growth.
The Rapitest soil test kit is commonly available, costs less
than $20, and comes with enough components to make 10
tests. The LaMotte soil test kit is one of the most accurate
available and can currently be purchased via mail order for
less than $55. When preparing a bed, I recommend adding
enough organic fertilizers to make all three major nutrients
“sufficient.”
Organic fertilizers are a better choice than synthetic ones for
several reasons. Organic fertilizers break down more slowly
so they stay in the soil longer and help build the organic
content of your soil as they break down. Synthetics can
certainly get the job done in the short term, but they also carry
