Veggie production slows to a feeble crawl as winter sets in, but below ground, microorganisms in the soil keep working year-round. To support this process, you can mulch over beds with leaves, grass clippings, straw, or another biodegradable material, or grow cold-hardy cover crops. 

Letting your beds go through winter naked is a cruel option that exposes soil to the triple threat of compaction from rain and ice, erosion caused by wind and water, and nutrient loss from leaching. Mulches and cover crops cushion and protect the soil, and as they decompose they improve the soil's ability to retain nutrients by increasing its organic matter content.

Use leaves, stockpiled grass clippings, old hay, or whatever you have to tuck in your beds for winter.

Consider Your Options

At this late date, mulch is the most practical option for most of us. Use whatever you can get your hands on, and pile it on thick. You can keep mulching all through winter if you don't have snow, because there is no such thing as too much winter mulch. In spring, when you want your beds to dry out and warm up, simply rake the mulch into pathways, or pile it up and re-use it later on, when your plants are up and growing. 

Hardy grains including oats, rye and wheat make great winter cover crops because their extensive roots do a good job of improving the soil's structure, and they will often germinate in cold soil. If you have a small garden, try sowing small patches using handfuls of whole grains purchased at the health food store. The seeds will sprout during mild breaks in the weather. In spring, you can chop the plants into the soil or pull them up and compost them.

Nitrogen-fixing legumes are an even better choice, particularly hairy vetch, Austrian winter peas and crimson clover. These crops need a bit of a head start in fall (planting dates range from September in the North to October in the South), but if you can get them established before winter, you'll have a dream situation in spring. Simply use a sharp hoe to sever each plant at the soil line. Let the foliage dry into a mat for a few days, and then make openings in the mulch to plant your veggies.

What are your beds wearing this winter? Use the comments section below to share your favorite winter soil-soothing techniques.

Winter wheat grown from bulk-bin wheat berries make a fine winter cover crop in a small garden.

'Tis the season for harvesting leaves, the most abundant free source of organic matter available to most gardeners. Microorganisms in soil and compost transform leaves into bits of organic matter, which helps the soil retain nutrients and moisture.  By themselves, leaves contain small amounts of 16 plant nutrients.

You can stockpile leaves in a bin or pen to use later as compost or mulch, but you don't have to wait until leaves decompose to put them to work. With some shredding assistance from your lawn mower, you can give your leaves useful jobs right now.

1. Turn lawn into garden. Prepare sections of lawn you want to develop into garden beds by smothering them with leaves. First scalp the grass by mowing as close to the surface as possible. Then cover the space with several thicknesses of newspaper or cardboard, and cover the base layer with two inches (or more) or compost or manure. Top with 3 to 4 inches of shredded leaves. 

2. Winterize hardy vegetables. Use shredded leaves to limit winter injury to kale, leeks, carrots and other hardy vegetables. Surround the planting with a low fence or burlap enclosure and fill it with up to 12 inches of shredded leaves. Mulch garlic and perennial onions with up to 6 inches of shredded leaves mixed with the season's last grass clippings.

3. Bury them in a trench. Improve the drainage and organic matter content in garden beds by digging narrow trenches, filling them with shredded leaves, and then covering them up. By late spring, the leaves will be sufficiently decomposed to mix into the soil, or you can plant right into the enriched trenches.

4. Mulch-mow them into your grass. Research done at Michigan State University reveals that when rather thick layers of leaves (to 12 inches) are shredded with a mower and allowed to rot where they fall, the grass greens up faster in spring and grows better the following summer. Just don't expect the leaves to disappear from view until the grass starts growing next year.

5. Mulch your trees. Stockpile shredded leaves until early winter, and then tuck in trees, shrubs, and perennial beds with 3 to 4 inches of shredded leaf mulch. A thick leaf mulch helps moderate soil temperatures in winter, reducing cold-related injuries to shallow roots. Beneficial soil-dwelling fungi are also abundant beneath shredded leaf mulch – one reason why Colorado State University lists mulching among its Ten Commandments of Planting Trees.

There is one precaution: Be careful with black walnut leaves, which can cause reduced growth in many plants, including tomatoes. According to Iowa State University, the juglone in black walnut leaves is usually neutralized by 4 to 6 months of composting.

Do you have other leaf-handling methods that work great at your place? Be sure to share them in the Comments section below.

As the summer winds down, you may be ready to let some of your garden beds go until next spring.

But wait! Before you call it quits for the year, consider cover crops. Now is a great time to sow a cover crop or two that will enrich your garden soil over the winter. It's a remarkably easy and inexpensive way to improve your soil.

Oats are one simple choice for a fall cover crop. Just visit your local garden or farm supply store to pick up some seeds and get them in the ground now. The oats will grow quickly during the cool days of fall, and then winter temperatures will kill them in most regions, leaving a soil-protecting mulch. (In warmer zones, you'll need to turn the oats under in the spring to kill them.)

Other good choices for fall cover crops include Austrian field peas, barley, crimson clover, rye, vetch or winter wheat. If you need a source for seeds, a good one to try is Peaceful Valley Farm Supply. Want to learn more about cover crops? Check out these helpful sources:

Cover Crops for Home Gardens This cover crop cheat sheet from Oregon State University is a quick way to figure out what to plant when. 

Eight Strategies for Better Garden Soil This recent Mother Earth News article from writer and homesteader Harvey Ussery is a great overall summary of how to improve your garden soil, including specific cover crop suggestions. 

Overview of Cover Crops and Green Manures This publication from the National Sustainable Agriculture Information Service explains all the details of cover crop use, especially as it relates to farmers and market gardeners.

It's easy to overlook how useful grass clippings can be, but early fall is a great time to collect this valuable 'yard waste' to use in your garden as mulch.

That's because as the weather cools, the grass starts growing faster and needs more frequent mowing. Sure, you could bag all these clippings and set them out to be hauled away with your trash. But why let them go to waste? A much better use is to put them in your garden as mulch. And don't stop with grass clippings — shredded leaves make great mulch, too.

Not only does this all-natural mulch help suppress weeds and retain moisture, but as it slowly breaks down it will naturally enrich your garden soil. Mulch is so valuable for your garden that you might even consider collecting unwanted yard waste from friends and neighbors — anything beyond your immediate needs can go into the compost pile. (Just be sure not to use grass clippings from chemically treated lawns. You don't want to introduce herbicide residue into your garden because it's harmful to your plants.)

For more about how and why to start using grass clippings in your garden and yard instead of throwing them away, check out this helpful information on recycling grass clippings from the Virginia Cooperative Extension. Or for more tips on composting your yard waste, check out the Mother Earth News article, Composting Made Easy.