I tried rye grass as a winter crop one year, and won't do it again. It
grew quite well, but in the spring my garden looked like a hayfield, and
cutting the rye grass and turning it under was quite a bit of work. I
don't have a scythe or a machete, and even my old power mower wouldn't
cut it, then the rototiller kept jamming as the rye grass clogged the tines.

There are far better winter crops to help your soil with less work.

wrote:

Someone said that planting rye grass in the winter (Pittsburgh) where
you have your garden would be a good idea because it replaces or adds
nitrogen to your soil. Right now I cover my garden area with leaves,
and then dig them in during Spring.

Tom