Another source of organic manures, altogether too little appreciated,
is what is termed "green manuring"--the plowing under of growing crops
to enrich the land. Even in the home garden this system should be taken
advantage of whenever possible. In farm practice, clover is the most
valuable crop to use for this purpose, but on account of the length of
time necessary to grow it, it is useful for the vegetable garden only
when there is sufficient room to have clover growing on, say, one half-
acre plot, while the garden occupies, for two years, another half-acre;
and then changing the two about. This system will give an ideal garden
soil, especially where it is necessary to rely for the most part upon
chemical fertilizers.
There are, however, four crops valuable for green-manuring the garden,
even where the same spot must be occupied year after year: rye, field
corn, field peas (or cow peas in the south) and crimson clover. After
the first of September, sow every foot of garden ground cleared of its
last crop, with winter rye. Sow all ground cleared during August with
crimson clover and buckwheat, and mulch the clover with rough manure
after the buckwheat dies down. Sow field peas or corn on any spots that
would otherwise remain unoccupied six weeks or more. All these are sown
broadcast, on a freshly raked surface. Such a system will save a very
large amount of plant food which otherwise would be lost, will convert
unavailable plant food into available forms while you wait for the next
crop, and add _humus_ to the soil--concerning the importance of
which see Chapter VII.

Using Humus to Increase Soil Moisture VARIETIES facebooktwittergoogle_plusredditpinterestlinkedinmail