Domestic Vegetable Gardens: Making Use of Cover Crops
A cover crop is a crop not intended for harvest, managed to maintain and improve soil fertility, water quality, and help manage weeds, pests, and diseases. Cover crops are an essential tool for home gardeners, offering numerous benefits to the home vegetable garden.
In the home vegetable garden, cover crops can be direct-seeded and prepared by removing dead foliage and weeds, raking or tilling the soil to provide good seed-to-soil contact, and broadcasting the seed. After sowing, the seed should be covered to a depth of 1/8 to 1/4 inch and lightly raked or dragged. Gently irrigate, keeping the upper inch of soil moist until the seeds germinate, then water less frequently but deeper until seedlings reach 1-2 inches tall.
The best timeframes for home gardeners to utilize cover crops are in the fall after the last harvest, in summer between cool-season crops, or for an entire growing season. Planting cover crops in the fall should be done from late August through early October, depending on the cover crop. In the spring, planting is done in early to mid-spring (April to May).
Summer vegetable gardens can benefit from fast-growing cover crops planted after the spring harvest (late June to early July) and terminated 2-3 weeks before fall planting, usually by mid-August. Vegetable gardens have fallow periods, such as after the fall harvest, before spring planting, or during the summer between spring and fall cool-season crops.
Understanding your goals for cover crops helps you choose the best species for your needs, as different cover crops address various benefits at different levels. A well-rounded cover crop mix for a home vegetable garden might be:
- Oats (grass) — early quick growth
- Buckwheat (broadleaf) — fast cover, nutrient accumulation
- Clover or hairy vetch (legume) — nitrogen fixation
- Mustard or other brassicas (optional depending on needs) — weed and pest suppression
This combination ensures soil protection, fertility building, weed control, and pest suppression while being manageable in a home garden setting. Seed mixes are often available commercially that combine these species for ease of planting.
Additional useful mixtures for fall or between-season cover include hairy vetch, ryegrass, and buckwheat to suppress winter weeds and improve soil organic matter. For summer vegetable gardens, a mixture including a fast-growing grass like sorghum sudangrass (builds organic matter), a legume such as sunn hemp or cowpeas (nitrogen fixers), and a broadleaf like buckwheat (fast cover and pollinator attractor) works very well.
Proper planning and understanding of factors are important to ensure gardeners get the greatest benefit from cover crops, so as not to interfere with the planting of vegetable crops. An exit strategy, or termination, is one of the most important considerations when growing a cover crop, as cover crops that are not properly killed at the appropriate time can become significant and difficult weeds. To prevent unwanted seed germination in subsequent growing seasons, cover crops should not be allowed to set seed. Terminate crops about a week after flowering starts, or mow the flowers off before or just after they bloom to avoid seed set.
References:
[1] https://www.extension.umn.edu/garden/yard-garden/articles/cover-crops-for-home-gardeners.html [2] https://www.gardenmyths.com/cover-crops-help-soil-fertility/ [3] https://www.motherearthnews.com/organic-gardening/cover-crops-zmaz0803 [4] https://www.extension.wisc.edu/garden/articles/cover-crops-for-home-gardeners.htm [5] https://www.almanac.com/gardening/cover-crops
- With cover crops direct-seeded and prepared in the home vegetable garden, gardeners can maintain and improve soil fertility as well as manage weeds, pests, and diseases.
- In the fall and spring, gardening enthusiasts can plant various cover crop species, such as oats, buckwheat, clovers, and mustard, to ensure soil protection, fertility building, and pest suppression for a manageable garden setting.
- By terminating cover crops at the appropriate time, gardeners can prevent unwanted seed germination in subsequent growing seasons and avoid having cover crops become significant and difficult weeds in their gardens.
- Seed mixes are available commercially that combine various cover crops, such as oats, buckwheat, and clovers, for ease of planting in home vegetable gardens.
- Choosing the best cover crop species for one's needs involves considering factors such as growth rates, nutrient accumulation, nitrogen fixation, and their impacts on soil organic matter, weeds, pests, and wildlife in a home-and-garden or gardening lifestyle context.
