Planting a fall cover crop is a little tricky around here.
Yes, there are winter wheat fields being planted right now by the 1,000's of acres. However, those wheat plants won't amount to much and might even be hard to till under in the spring. A gardener may have just planted a "weed" for 2013 instead of a cover crop.
That is certainly how the traditional winter rye can turn out. Always be sure that it is
annual rye seed that you are buying or you have just sown a lawn in your garden space.
Okay, you have your
annual rye or wheat weed. I have found that rye can be waist-high by the end of April
IF it is planted by the end of July . . ! Try sowing it here in September and it will be ankle-high by that time . . . I'll take the waist-high stuff and pull it by hand - then, it needs to be buried in the planting beds.
Don't want to tie up your planting beds from the end of July on? That's understandable. You aren't going to get much out of the way except spring greens and peas by that early. Still, you can see how you could do a 3 year rotation with a winter cover crop:
1st Spring: peas or early greens
Summer: winter rye
Fall/Winter: grow on
2nd Spring/Summer: warm-season veggie
Fall/Winter: fallow
3rd Spring: peas or early greens
. . . . .
Another idea is a spring cover crop: peas and something like mustard.
Finally, there is a summer cover crop: something like sunflowers that are chopped and tilled before bolting to seed.
I wish I had more options for a late sowing but I don't really. Only about 10% of Austrian field peas sown late survived our sub-zero winter. A gardener could consider the
seed as an "organic fertilizer," I guess.
Steve