Cover your bed with crops? : LUSENET : TimeBomb 2000 (Y2000) : One Thread

I think it was Brooks who mentioned cover crops in another post. Sorry if I misremembered. Here's a very useful, save-work, related article from National Gardening, Jan/Feb 1994:

"Let decaying crops lie, is the word from USDA researchers in Oklahoma.

In a laboratory test, S. J. Smith and A. N. Sharpley measured nitrogen released from three types of green manures--alfalfa, wheat and sorghum--on eight soil types. . ."

There was no difference between leaving the cut cover crop on top of the soil and tilling it in. Nitrogen runoff was essentially the same.

-- Old Git (, April 23, 1999


Warn't me, but I'm truly honored that you associated me with a gardening tidbit. I haven't used cover crops myself, mostly because tilling them in seemed too much of an effort (and might not be possible in my current raised garden setup). Great to see there is an option. Sounds similar to Ruth Stout's "no till" gardening. I do believe the most important gardening technique is working as much organic material into the soil as possible, and cover crops are a time-honored way of doing that. I have transformed the glacial cement in my backyard into luscious loam, crawling with crawlers. "Feed the soil, not the plants."

-- Brooks (, April 23, 1999.

Certain plants have "nitrogen fixing" properties - among them the legumes (cover crops). They turn the nitrogen into a form other crops can absorb.

My soil is hard clay. I like to turn raw organic material into it in the fall. When it breaks up, the organic matter acts like little sponges in the soil to retain moisture and creates tiny little pockets of air. It prevents the clay from re-packing. This allows good root growth and absorption of nutrients and water in the plants. One could just leave the dead matter on the soil and it would still decompose, but I imagine it would take longer to "build up" a hard soil that way and would affect only the thin top layer instead of getting deep into the lower layers by turning it over or tilling. "No till" is promoted as an erosion control device, because the roots hold the soil from sheet or flood erosion.

Without the high presence of nitrogen fixing bacteria, the raw organic material doesn't break up and decompose as fast. When it first decomposes, there is a drop of available nitrogen. That is why I turn the raw matter under in the fall, leaving the moisture of winter and warmth of early spring to decompose and replenish the useable nitrogen capacity of the soil before I plant my veggies.

After my seeds are up and thinned, I will apply a mulch of straw around them to retain moisture and cool soil temp. (Some do this with black plastic "mulch.")

I am not a farmer - just a gardener. I imagine that no till works best when there is already a good deep layer of established soil and you are just trying to replenish nitrogen and prevent erosion.

I would think that the root mass and dead litter buildup would diminish available sun and space for small new annual seedlings. Correct me if I am wrong, but no till might be more appropriate for hardy perrenials like pasture (20 years), clover or alfalfa (7 years).

-- marsh (, April 24, 1999.

Marsh, I think you're probably right. Although the article didn't specify the type of ground used, it was probably cultivated. However, I read somewhere that the roots of plants can have a beneficial effect on clay soil, so perhaps there's soemthing in that too.

Brooks, I'm with you on the square foot idea and on heavy mulching (after the soil has warmed up). I've read articles by and about Ruth Stout--she must have been a fascinating woman. I've got two large planters, about 4 x 3', which I use for planting tomatoes. They can be planted closer than usual of course because I can keep the soil very rich, amd they don't need mulch because the plants crowd out weeds. It's very easy to wrap them in bubble wrap when frost threatens--that's how come I was picking tomatoes in JANUARY of this year. Would have picked longer but I got fed up of wrapping!

-- Old Git (, April 24, 1999.

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