Most gardeners would love to have fresh produce year round, and it's possible if you plant gardens all year, even in the winter. A winter vegetable garden can produce a wealth of bounty that is hardy to the cold temperatures, snow and rain in many areas. The key to a successful winter garden is location and protection from the worst winter has to offer.
Choose vegetables that will prove hardy in your region. Root-type vegetables such as beets, globe onions, turnips and radishes are favorites, as is spinach and carrots and some bean and pea varieties, depending on their climate limitations. Head-type vegetables such as cauliflower, cabbages (including Chinese cabbage) and Brussels sprouts may also do well, depending on your region and climate.
Seeds for winter gardens must be planted a little deeper than those sown in summer, around two inches deep. This will help protect them from frost. Many root vegetables, such as turnips, globe onions and carrots, do just fine during winter months. Seedlings or sprouts may be planted as usual and then protected with coverings.
Mulch the garden area well after planting to help keep soil warm, but be prepared for harvesting smaller vegetables, because mulch will also block out light. The key is to mulch before the ground freezes. Check the Farmer's Almanac or other planting guides for the anticipated first freeze in your region.
Protect the garden from cold winds. Putting up some type of windbreak or planting your garden near a wall will help warm the soil by 10 to 15 degrees. South-facing walls are best. Protect plants with cold frames, which can be built with 1x2s or 2x4s in a box shape, 18 inches tall at the back and 12 inches at the front, then sealed with fiberglass or polyethylene and placed over plants. Some gardeners use cloches, miniature greenhouses that you can buy or make yourself using empty liter-size clear plastic soda bottles or milk cartons. For added protection against the cold, add a layer of mulch to the garden area, such as straw to help provide insulation and protect soil from heavy rain or snow melt.
Plant winter vegetable seeds in a different location than your summer garden to avoid weakening your soil and losing nutrients. Ideally you should rotate garden crops yearly, or find different areas of your yard for your vegetable garden at least every other year.