Agriculture Reference
In-Depth Information
The reason why I detailed testing biological activity before
discussing analysis of macro-nutrients is because, with regard
to nitrogen, the amount of nitrogen you need to add is
modified depending upon the amount of biological activity.
DNA and other proteins present in soil microbes contain
nitrogen that will be made available to plants throughout the
course of the season, but won't show up in a soil test because
a soil test only shows inorganic nitrogen. The amount of
nitrogen to be added according to soil test assumes a certain
level of biological activity, but if your level of biological
activity is greater than the assumed level, you should add less
nitrogen than the test recommends. Conversely, if your
biological activity is less than the assumed level, you should
add more nitrogen than the test recommends.
In general, I recommend using at least two sources of a given
macro-nutrient. This will distribute a greater variety of
accompanying micro-nutrients and because the sources will
break down at different rates, they will provide nutrient
