You don't say what zone you live in so I will tell you what I do in zone 7. I till in the fall and plant a small crop of english peas or soybeans. I layer on about 1 inch of mulched leaves and leave it until the peas come up. I also start a compost bin and remember to mix it up or turn the compost with a garden fork every week. In January if the soil is warm (as long as it is not frozen it's okay) I till the peas and leaves under. The leaves and the peas add much needed organic nutrients. The tilling in the cold weather brings up bugs and their eggs which have burrowed underground for protection and kills them. In March I till the soil again adding in some manure and "composted" organic materials (leaves, vegetables, coffee grounds, eggshells, etc.) Make sure this has been fully composted. Your garden should be very healthy for planting peas, broccoli, cabbage, geens, etc. at this time.
