Get your garden ready for winter
You might have harvested the last vegetables and picked the last flowers to save them from the frost, but your garden still needs some attention before the snow flies. By completing a few clean-up chores now you can head off some disease and insect problems and enhance soil quality.
If you've noticed serious disease problems on any of your plants, now is the time to remove the diseased foliage and spoiled vegetables or fruit. Many diseases survive well over the winter on plant residue and will infect next year's crops if the residue is left in the garden. Even composting won't kill some diseases, so consider starting a separate "dirty" compost pile to handle diseased plants without contaminating the compost you return to your garden.
Insect pests can also survive over the winter under plant residue, so even if the residue is healthy, it's best to remove it or chop it up and work it into the soil surface. That way the residues can start breaking down over the winter, adding organic matter to the soil. Fall is a good time to add lime, compost, or manure to garden soils, too. Most other fertilizers are best applied in the spring, but fall is a good time to collect soil samples and send them in for analysis. That gives you time to get results back and make plans for application next spring.
Even though it's a good idea to remove plant residues or work them into the soil surface, leaving the soil surface unprotected can result in wind or water erosion over the winter. One solution is planting a cover crop such as annual ryegrass. As long as it gets a little moisture, annual ryegrass will emerge about a week after it is planted and it quickly forms dense roots that help store soil nutrients over the winter. The roots also help break up surface compaction and provide a habitat for beneficial soil organisms including earthworms.
A cover crop can also help block out perennial and winter annual weeds that become established over the winter or early spring. Even if you choose a cover crop that is killed by winter weather, the plants will continue to protect the soil surface. In the spring, the cover crop can be turned under, adding additional organic matter to the soil.