Tuesday, January 6, 2009

Cover Crops

Rarely have I used cover crops. But almost everything I read recommends them either for enriching the soil or weed control. This past year I did plant winter rye in most of one bed. It grew thickly and quickly. Other than that I have left the garden beds empty for the winter. I have never planted a cover crop in the spring.

Now I see that there are cover crops that can be planted in the spring and turned under in the summer so that a fall crop can be planted in the same bed. One recommendation for a spring cover crop is buckwheat. There are also cover crops that can be planted in the summer and turned under in the fall. One source recommended sweet clover. Annual rye can be planted in the late summer and turned under the next spring. It apparently does not survive the winter and I am not sure why it would be preferable to winter rye. The only recommendation of winter rye I have found is in Rodales All-New Encyclopedia of Organic Gardening where it is listed for late summer or fall planting. That book also lists annual ryegrass for spring planting where other sources list is only for fall. I believe I planted annual ryegrass one year and it did not do well.

I need to make a note to dig the winter rye under in early spring - probably about the same time as the garden is ready for spinach and other early spring crops.

Winter rye and buckwheat would be "green manure" as opposed to alfalfa or clover that are legumes and add nitrogen to the soil.

Soybeans are also listed as a green manure. I assume that means that when my soy beans have been harvested I should dig the plants into the soil as opposed to adding them to my compost pile. Or do I dig the roots into the soil and put the rest of the plant in the compost pile? Another question to try to answer.

So now back to the garden plan to see what is appropriate to plant in the spaces that have been left for cover crops or that have only a spring or a fall vegetable crop.


  1. Hi John,

    You have a bunch of good questions. First, here are a list of cover crops you can plant in late spring. These are "tropical legumes" for controlling weeds and adding N; lablab, cowpeas, sunn hemp, and as you said soybeans.

    I practice low-disturbance gardening. When killing your cover crop you want to avoid regrowth since regrowth can compete with your vegetables. So, cut your cover crop to the base when it was flowers! Most of the time it won't grow back.

    This requires timing of planting and killing.

    Hope this helps!

  2. Also, your cover crop can then be used as a mulch. To add additional N, I add feather meal and/or fish meal.

    No digging needed. Unless you like digging.