Agriculture Reference
In-Depth Information
How to Seed and Care for Cover Crops
Cover crops are just plants. They're cared for much the same as other plants. If you're
using them in a vegetable garden in the fall, they should be seeded right after your main
harvest time or even a week or two before your harvest. Of course, many of us grow a mix-
ture of vegetables that we continuously harvest, and in that case we just plant the cover
crop towards the end of the season. I like to plant fall cover crops a couple of months be-
fore frost to get them firmly established.
If possible, it's best to get seeds into the soil. Small-seed legumes go about ¼ inch deep
while larger seed legumes and small grains are planted 1 to 1 ½ inches deep. While gener-
ally not as successful, you can broadcast the seed for small-seed legumes on the soil at a
higher rate and you should get germination if you keep the soil moist for the next week.
You'll probably be cutting down your cover crop before you seed or transplant. Farmers
mostly do this with herbicides, but you can just use a hoe or various other tools. It's not a
bad idea to leave some of the plants alive to produce seed, attract insects, and for many oth-
er benefits, but most of it will be cut down. It's generally a good idea to wait two to three
weeks before you seed and one week before you transplant, to reduce allelopathy and po-
tential predators and allow some nitrogen release from the plants. That being said, some
cultures have kept soils going for thousands of years by skipping this downtime. If you use
fish emulsion, you can spray that on the cover crop when you turn it in order to hasten de-
composition.
We'll look more at tilling in a later chapter, but I'll mention here that you can lightly in-
corporate your cover crops into the top few inches of soil a couple of weeks before you
plant. I believe in disturbing the soil as little as possible through no-till or low-till practices,
but it's a good idea to lightly work a green manure into the top layer of soil to speed up the
decomposition and decrease the amount of nitrogen lost to the air. Residue from a grass/
legume mix will have a higher carbon to nitrogen than the legume alone, slowing the re-
lease of nitrogen so it's not as vulnerable to loss.
