you can plant small grains. Oats will grow in the fall and freeze out over the winter. Wheat or rye can be started in the fall and will over winter and come on strong in spring. I seeded oats about a week ago under growing plants and covered it with a little compost. it is coming up and will be well established when the crop ferezes out. You could also seed vetch which will overwinter.

Fava beans will grow until the temps are well down in the 20's.

What you want now is a cover crop that will grow some in cool weather, stay in place over the winter and grow a bit more next spring, something that will help hold your soil in place during the winter. That means knowing a bit about which cover crops will do that.
Oats are seeded in the spring to grow during the summer, they need warm weather and are killed by frost.
Buckwheat is the same.
Wheat maybe, depending on which wheat seed you get. Many of the wheats have been genetically modified and may not be something you would want, and that seed is fairly expensive which is why that is seldom listed on Cover Crop lists.
Most clovers prefer to be spring seeded so the have time to get established before winter sets in.
Fava beans, and Austrian Peas, like to grow in cooler weather, but are killed by really cold weather so only dead plants would be left on the soil during the winter.
Winter, Field, Cereal Rye, "Secale cereale", is one grain that germinates well in cooler soils, grows 4 to 6 inches tall, and then stops growing until the soil warms up. This helps hold your soil in place if snow cover is insufficient to keep surface soil from blowing, eroding, away. This is one of the few grains, or cover crops, that will stay alive, along with Winter Wheat, and will actually provide cover, the reason you plant a cover crop, for your soil.

Kimm, I've learned a bunch from reading your posts even though you are further north than me. I disagree that oats are only for spring. True, they freeze out. But here in zone 6b they get quite a bit of growth before they freeze. By then there is good cover to catch the snow and protect the soil. In the spring, if your soil is in good enough shape for no-till, your bed is already mulched. If not, there is still lots of organic matter to turn in.

Last fall I planted a mix from Peaceful Valley that contained oats, peas, fava beans, and vetch. The earlier sowings grew so lush with the oats, peas and fava beans that the vetch never stood a chance. Really good erosion control. The later sowings had less oat growth before freeze, but the vetch lived through the winter with plenty of cover for the soil and green material to turn under in the spring.

Being a newbie, I can see the benefit of a mix especially for the first year. You can see what works in your zone and for what planting time.

Kimm, a question.. did last winter's nice cozy cover contribute to the flea beetle infestation this summer? Is this the dark side of cover crops?

Fertilizersalesman, thanks for the idea about seeding under growing plants. I have some okra that is producing too well to pull up. I will seed under the okra with wheat or rye.

I consider winter-killing a bonus. In fact that's the point of planting oats in fall, or buckwheat. You get both soil enrichment and ground cover/erosion control, and won't have to battle the cover crop in spring. Annual rye is another good late-planted cover but doesn't reliably winter kill in this zone.

We planted buckwheat this fall which is now blooming. Since it's too wet to till it in I'm going to take a chance - let the frost kill it, then expect a self-seeded crop next spring which will be easy to kill with a single tilling. Fingers crossed.

Would it be too late to plant a fall green manure mix that contains winter rye, field peas, ryegrass, crimson clover and hairy vetch? I am placing an order for some other things from Johnny's and I was thinking of adding this if it was not too late to seed my now empty squash beds. Is there enough time to grow this? The weather has been in the 80's this week, which is very weird for this time of year, but it can't last forever.

There are too many variables to know whether any one thing contributed to a particular pests population explosion. The mulch may have provided a prtoective habitat, but that would also be true for any predators. I've not seen a problem with pests in any year I've had mulches or cover crops on the soil. We did have major problems with pests the first 5 years we lived here until I started to get adequate levels of organic matter into the soil and the nutrient load started to balance out.

liv2learn,

Small grains are typically planted late September, early October. You should be fine with the rye and rye grass. I suspect you are not too late for the legumes, but I am certain.

Hi,

I used hairy vetch last fall planted on the 6th of October here in the Northeast. I was able to get germination and enough growth for it to winter over for me. In the spring it came back and grew well and I turned it under easily and planted tomatoes in a couple of weeks. I liked it very much and tried it again this year only sowing it in mid September.

It is up and doing fine. I am also planning on trying some in one of my beds as late as next week when I pull my tomatoes. Very late, but I am experimenting. I always have tomatoes coming out of the garden late.

If the grain you plant is killed off before winter even begins then it is not a winter cover crop. One of the reasons for planting a winter cover crop is to aid in holding your soil in place so the winter winds do not blow the soil away, and if there is no growth the soil will not be held in place, unless what was seeded was so thick that it was more like a mulch after the cold weather killed it off.

A thickly planted, winter-killed crop's roots plus its thatch of dead leaves = cover = erosion control, unless you're growing on a slope. For large areas you do not want to turn over by hand or till in the spring this is good.