Well, I don't know if that's really quite the right way to look at it. A cover crop is just "compost in the raw" -- it will work the same way once it breaks down.

Its just that compost is something you can't ever really have enough of in a garden, because it too is constantly breaking down, and the nutrients being used. So, the more the better.

Composting AND green manure -- that's the way to go.

Yes.........Kind-of ;-)
Really depends on what you are trying to accomplish with the compost, I add boatloads to my beds every year, (because of shrinkage),and if I grew a cover crop it may enhance my growing medium,but it wouldn't supply any additional bulk,so because of shrinkage,I have to add additional medium/compost to fill up the beds, if you are growing in the ground,you might not need any additional bulk, so a good cover crop would supply all kinds of benefits...Nitrogen Fixing,as well as keeping the soil food web happy ,because you are using the land with a deep rooted cover crop.

If you don't have equipment to break up winter/cover crop roots it can be useless depending on what you plant.

It depends on the biomass you produced. In another thread I suggested favas, and at your site favas will produce 6ft tall thickets by May. That is a lot of high N biomass, you mow it and mix it with fine wood chips (about 3/1), it will compost relatively quickly.

For northern areas forage radishes can make a nice top growth and a beautiful in-ground growth that winter kills off.

I was talking to a local farmer about this, the guy who introduced me to materializing the soil. He follows a model that says it is best and only to cover crop and that only applying compost always creates an imbalance. Interesting. He sends his soil to be tested regularly. I think it is knows as the High Brix method. Didn't look it up but I am going to do more cover cropping (and continue to compost).

There is no way someone farming multiple acreage could possibly produce sufficient compost to develop or maintain soil humus. I can't do it on fractional acreage even with external feedstocks.

Jonhughes is an exception!

Cover cropping gives a YES answer to your question. As Wayne notes, forage radishes are the rage around here as they get winter killed and rot in ground leaving top mulch. Appropriate sowing can make up deficiencies.

Cover crops...

If you are a home gardener with limited equipment or space, choose your plant cover wisely.

I know way too many people who thought this would be a wonderful idea only to find themselves faced with a mass of roots and plant matter in/at the soil level keeping them from working the soil when spring hits.

Many cover crops need some kind of soil disturbance or killing rest after the tops are harvested before you can use the soil again.

Maybe I am under the wrong impression? I pictured it this way: sow a cover crop like rye or red clover into my raised beds this fall. Let them stand through mid winter, and then turn them into the soil in mid February. That would give them six weeks to rot in before spring planting in early April. My beds are not really conducive to tilling. I tend to use hand tools for everything because I like the peace and the exercise. Would the root systems make it too hard to do this with hand tools?

It's not that I do not have compost. I do. It's just that it takes all I have for my vegetable garden, and I have ornamental gardens too that could use it.

As I understand it, cover crops can only add back organic matter and if it's a legume crop, nitrogen. Further, they can prevent erosion and leaching which may be of considerable value. Other than that, I would think that you have to replace what you are taking out. Your harvested crops remove many minerals from the soil which sooner rather than later will need to be replaced. Although I've heard that deep rooted crops like alfalfa can bring up minerals from the subsoil. But in general, minerals are removed by your vegetables and cannot be replaced by cover crops. Something has to give.

tcstoehr that is why you cover crop and remineralize at the same time. The idea is that you are never leaving your soil bare, that there is always living material growing in it because the soil is alive and needs all those layers of micro and macrobiology.

Donnabaskets, you'd be mowing your "grass" cover crops at least once for the winter. A great yet productive winter cover crop is broad beans. You would grow them, you can harvest the beans and then you'd cut up the green material, till/turn it under and plant in two weeks. In general, the farmers around here plant 2 weeks after turning under a cover crop. I have several friends who practice small urban farming with sustainable land stewardship. They have slightly larger properties than you'd have in your garden :) Joe rolls his grains down a few times a winter before tilling. Essentially from one set of cover crop seeds he then gets 3 crops because the broken stalks sprout again by the soil line and he can roll again. It's amazing. His farm was almost washed away a few years and with this method he was able to farm again within a few months.

The above posters are right: it's really, REALLY hard to replace all the nutrition you take off the soil via vegetables/fruit, and replace it in equal measures.

Remineralizing is important, most people don't know how much. Cover crops can replace a certain %, and compost can help, too. But there's no easy fix.

Either do your homework by reading about cover crops, or contact your local Cooperative Extension Service/Master Gardener and ask some questions: What cover crops grow best there (winter? spring? summer? fall?)? Do you get enough cold there in winter to kill off any of them? Are there some that will grow through winter? Which ones are easiest to knock down or to till in? What do each of them provide: nitrogen? bulk organic matter? root mass? top growth?

Emphasize you grow organic, or they may fail to tell you that a certain plant is usually killed by herbicides by the chemical farmers, and then you're stuck trying to manually kill or till a heavy root system.

How large are your beds, and how many do you have?

One trick I learned kind of accidentally: I had several beds that turned into masses of weeds when I was sick for a month. I had acquired a stack of heavy cardboard by luck.

My angel neighbor weedwhacked my beds. While I was still recuperating, I would drag maybe one sheet of cardboard a day to my beds and cover them, putting some rocks on top to hold the cardboard down. The cardboard partially deteriorated over the winter, but by spring, the beds were mostly BEAUTIFUL, with just a few weeds. The worms and creatures had been digging around under the shelter of the cardboard most of the winter, the weeds had disappeared, the soil was soft and dark. All I had to do was pull the few weeds, rake some organic fertilizer into the top few inches, sow my seeds. Easy!

So then I thought, why not do this with a cover crop? Sow the beds, let the crop grow, then whack them down in place (leave the tops on the beds), and cover them. With some of the more brittle cover crops (like buckwheat), you could probably just stomp them flat and cover them.

Get on your local FreeCycle and see if anyone has cardboard they want to unload. Old sheets of plywood works well, too, and it doesn't rot as fast. If the plywood has a few fist-sized holes in it, just slip double or triple thicknesses of cardboard under them. Lift and stack them against a back wall during the growing season. Or use black plastic, held down with rocks or bricks.

Sue

Correction: cover crops add no minerals whatsoever. And only those that fix N add any N. What they do, over the course of months, is generate humic acids that favor the absorption of nutrients that may be otherwise bound to, e.g., a clay particle. They may also nourish mychorrizal fungi, and these also help plants absorb nutrients.

What happened in the case of Sue was that most of the weed seeds sprouted, but the weeds had not formed seeds of their own yet. It is one of the best strategies for weeding, if you are willing to lose most of May and June(in MI). Then the cardboard killed them all, and the earthworms had a season-long banquet. Et voila', prime soil.

This is why I (and others) recommended favas. They are going to fix the most N, and they are going to generate the most biomass. Those are the only two things you can get. They will choke other winter weeds, such as chickweed. And their roots break clay but degrade faster than other cover crop roots. People in the Mediterranean have used them for thousands of years for a reason.

Thanks to you all for clarification. You have basically described what I (vaguely) had in my mind, so I think I am on the right track. Even when I put my good compost in the beds, I still fertilize too. My soil tests say that I am very high in phosphorous and potassium, so all I add is Nitrogen, this year in the form of blood meal. There were no mineral deficiencies found when the soil was tested last fall.

I have the advantage of very mild winters. Most weeks, I can get outside and work at least for a few hours on at least one day. I have 9 raised beds, each about 8' x 3.5'. I only grow crops in three or four during the winter, so I could use cover crops in the others. I am thinking maybe to use compost one year, and then cover crop the next. That way, I can use my compost in other needy areas of my garden too. But, I would still add compost in the spring to the beds that were growing crops through the winter. (It takes the entire compost pile to dress all my raised beds.)

Ggg, you recommend broad beans. Is that soy? I guess I do not know what that is. Bp, those are great questions and I will indeed call the County Extension on Monday. My experience has been in the past that they don't always have alot of info for organic gardeners. They mostly work with farmers and their first recommendation is for chemicals. To tell you the truth, I have gleaned far better information from the kind folks on this forum.
Glib, I will also check out favas. The forage radishes are intrigueing too. Perhaps I will try a variety of crops this year and do some comparisons.

Thanks to each one of you for your replies!

fava and broad beans are the same plant.