I often use oats or barley since they will freeze back once you get a hard freeze. In the south that might be a problem because it may not get cold enough. I also use cold hearty flowers because they will live all winter unless there is no snow. They are easy to kill by mowing and tilling. Such as: sweet alyssum, calendula, cornflower, foxglove, larkspur, pansy, stocks, viola, or dianthus