Oats might be one.

Herllo, Rollen...fellow Hoosier.
White mustard can be sown in March and tilled in in late April.

Winter rye works as well as oats.

I grew winter rye in the veggie bed for the past 3 years starting in the fall. It was amazing how well it grew by spring time... deep roots... tons of green matter (twas a bit of Ireland green in the middle of winter).

But...

I switched to and am trying for the first time hairy vetch and crimson clover this winter. The allopathic issues of winter rye cause a lot of issues for me in the spring since I couldn't get out to turn it under early enough due to the rain. I tried round after round of seeded spring veggies with only a tiny portion germinating for me. So to avoid the potential same issue next year... I switched.

The original poster wanted a cover crop that could be planted next year.

I prefer to plant a cover crop of daikon radishes in late summer. These will winter kill and leave a nice covering in the spring that isn't a hassle to plant in.

Where do you source the daikon seed ?

I stopped at at Albert Lea Seed Company in Albert Lea MN and bought a couple pounds of tillage radish, not sure if they will mail them or if you have to stop in.

prairiechuck,

I source them at Fedco. You can buy them in low as one pound and that will sow about a tenth of an acre....and likely keep for a couple years or maybe more.

I should have said that they sell them under "forage radishes" as tillage radishes is trademarked...you still get the real deal though. Mine are huge and will likely begin to freeze out soon.

This post was edited by wayne_5 on Wed, Dec 19, 12 at 13:59