In September you may have a garden of fall vegetables growing but if your garden is finishing up from the summer crops it’s time to plan for winter. You should always have your ground covered even if you don’t have a vegetable crop growing. There are two options for covering your garden in the winter. A winter cover crop can be planted to improve your soil or a thick layer of mulch will also benefit the soil. A cover crop is a plant that is beneficial to the soil like clover or vetch. Both of these plants are legumes and will fix nitrogen into the soil through a biological process. Rye, which is not to be confused with ryegrass is also beneficial because it grows large and will create lots of biomass that can be tilled into the ground the next spring. You can think of these plants as growing your own compost in the soil. You can plant a combination of these plants or use them by alone. Cover crops need to be planted in September or early October so that they can sprout and grow while it is sill warm. All three will survive the winter in Georgia but will only grow when it is relatively warm. An old rule of thumb that was passed along to me says that winter crops will only grow when the combined temperatures of the high for the day and the low for the day add up to 100 degrees F. An example would be 45 for low over night temperature and 55 for a high day time temperature with most of the growth being in the early fall and late winter or early spring. In the early spring you will need to cut these crops down before they go to seed and let them wilt on the ground for a few days to a week. They can then be tilled back into the soil to get ready for spring planting.
If planting a cover crop is not practical for you then I would suggest mulching your garden over the winter. Depending on what type of vegetable garden you have you can get ahead of the game by preparing your beds in the fall. Of course if you have boxes or square foot gardens that don’t need to be tilled and shaped then you have that work already done. We have found that shredded leaves are one of the best mulches for a garden because they usually don’t contain weed seeds and most of them will break down into compost over the winter if you chop them up with your lawn mower first. A layer 2 to 3 inches thick over the garden will benefit the soil and the plants that you put in next spring. Most of the time the soil will be so soft under the mulch that you can set out plants right through the mulch. If you are planting seed you will need to pull the mulch off ahead of seeding but after your seed are up and growing you can take the same mulch and spread back around your seedlings to help discourage weeds.