Winter weather can wreak havoc on vegetable garden beds. Cover crops not only protect the soil, but add fertility as well.
Many gardeners see Fall as the end of the gardening season: Pick the last of your tomatoes, peppers and beans and put a lid on it. But Fall is a critical season for your vegetable garden beds. They need to be protected from winter weather and prepared for the next growing season and the best way to do that is by planting a cover crop, also known as a “green manure”.
Before the invention of synthetic fertilizer, cover crops were planted in between harvests (not just over winter) to scavenge and store nitrogen and other elements, preserve soil structure, slow water runoff and evaporation, protect garden beds from erosion, and suppress weed growth. It’s a sustainable method overlooked by many home gardeners, but is widely used in organic agriculture.
Many different plants are used as cover crops: rye grass, oats, hairy vetch, clovers, winter rye, buckwheat, winter peas, forage radish (a.k.a. daikon radish ) and tall fescue to name a few. Cover crops are planted at different points in the gardening cycle – some in spring, some winter, some fall, but the intent is to let them grow until they winterkill or until the next planting cycle when they are tilled into the soil to provide nutrients, serve as a mulch layer and to increase soil tilth. Protecting your garden with cover crops is more effective than mulching, because they provide the added benefit of creating passageways for air and water via their root systems.
The choice of cover crop depends on a number of factors:
- what was planted in the soil bed most recently
- your geographic region
- condition of your soil (compaction, fertility, etc.)
- what you’ll plant in the same bed next season
- recent disease or pest problems
What’s appropriate for your home vegetable garden? The Old Farmer’s Almanac has an excellent, easy to understand chart of the best cover crops for your area.