Agriculture Reference
In-Depth Information
protect their host. Planting cover crops will serve to keep
these critters fed through the winter months and protected
from environmental hazards such as sun and erosion. This
way they are healthy and well fed for the next planting
season.
For these reasons, harvesting should be considered a two-part
process in which the task of harvesting is followed as soon as
possible with the sowing of cover crops, which can also be
known as green manures.
Green manures are plants grown specifically for the role they
play in sustaining soil fertility, but they also reduce erosion
and feed beneficial microbes outside the growing season. The
benefits of green manures on crop yield are far from merely
theoretical. In one study, for example, the use of hairy vetch
(a common legume) as a green manure and mulch increased
tomato yields by more than 100%.
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Green manures are
generally either grains or legumes; grains because of their
ability to pull nutrients up into the topsoil from a depth of
several feet,
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and legumes because of their ability to take
nitrogen out of the air and fix it in nodules in their roots,
thereby fertilizing the soil. They are either tilled directly into
the ground once grown or added to compost piles. Legumes
use up their stored nitrogen to make seed, so when they are
used as green manures, they need to be cut just before or
during their flowering. During the summer growing season,
green manures should be grown in beds that will be followed
by heavy-feeding plants, such as cabbage, as part of a crop
rotation plan.
An important aspect of making a mini-farm economically
viable is the use of green manures to provide and enhance soil
