phosphorus, potassium, magnesium, and sulfur, but is
especially important for trace elements. The important
principle is to return to the soil, by the use of plant
residues and manures, all that has been taken out of it.
Nitrogen storage—The compost pile is a storehouse for
nitrogen. Because it is tied up in the compost-breakdown
process, water-soluble nitrogen does not leach out or
oxidize into the air for a period of 3 to 6 months or
more—depending on how the pile is built and
maintained.
pH bu<er—A good percentage of compost in the soil
allows plants to grow better in less-than-optimal pH
situations.
Soil toxin neutralizer—Important recent studies show
that plants grown in organically composted soils take up
less lead, heavy metals, and other urban pollutants.
Nutrient release—Organic acids dissolve soil minerals
and make them available to plants. As organic matter
decomposes, it releases nutrients for plant uptake and
for the soil microbial population.
Food for microbial life—Good compost creates healthy
conditions for organisms that live in the soil. Compost
harbors earthworms and bene9cial fungi that 9ght
nematodes and other soil pests.