Agriculture Reference
In-Depth Information
= 50 oz.
Based upon these calculations, in order to make a complete
fertilizer for 100 sq. ft, I need to combine 50 oz. of greensand
with 28 oz. of soybean meal and 6 oz. of bone meal.
This fertilizer is a bit off from precisely what you need,
because soybean meal also contains a substantial amount of
potassium, and bone meal also contains some nitrogen. In
practice, this isn't a problem because the ingredients, being
organic, aren't instantly available to plants so a bit of an
overabundance won't hurt as much as it would if you were
using chemicals such as ammonium nitrate as fertilizer.
But if you were to use alfalfa meal and dried seaweed as
ingredients, keep in mind that they contain almost as much of
one nutrient as another, so using the easy technique could
lead to an overabundance of fertilizer. Though it might not be
an immediate problem, over the course of a season an
overabundance of some nutrients (such as nitrogen) can lead
to undesirable outcomes such as plants making all vegetation
and no fruits or tubers. Other nutrients in excess can block the
absorption of micro-nutrients. So a little bit of
over-fertilization is okay, but you don't want to go too far. If
you are using fertilizer components that contain substantial
amounts of more than one nutrient, then you'll be better off
using the more difficult method.
The solution is to use algebra to solve a system of equations.
The number of equations and variables is the same as the
number of ingredients. For a fertilizer composed of three
ingredients, the equations would be:
