Selecting Cover Crops for Home Gardens

Cover crops are an important tool for home gardeners to improve soil health and fertility, suppress weeds, and reduce erosion. By selecting the right cover crops for your garden, you can reap the benefits of improved soil structure, increased organic matter, and reduced pests and diseases.

Problem-Solving Cover Crops

Cover crops can be used to address a variety of soil problems, including:

• Nitrogen deficiencyNitrogen-fixing cover crops, such as clover, vetch, and peas, can add nitrogen to the soil through nitrogen fixation. Nitrogen scavengers, such as radish, rye, sudangrass, and sorghum-sudan hybrids, can capture excess nitrogen before it can run off.
• Poor soil structureCover crops with deep roots, such as tillage radish or daikon radish, can help to aerate compacted soils and improve water infiltration. Other cover crops that promote healthy soil structure include clover, vetch, rye grass, sudangrass, sorghum-sudan hybrids, and mustards.
• Low organic matterCover crops can add organic matter to the soil, which helps to improve soil structure, water-holding capacity, and nutrient availability. Succulent plants, such as legumes, break down quickly, providing nutrients but leaving behind little lasting biomass. Fibrous plant tissues, such as grasses and grains, break down more slowly, tying up nutrients but building stable organic matter in the soil.
• ErosionCover crops that provide good cover and a dense root system can help to stabilize soils and combat erosion. Cover crops like clover, annual rye grass, Austrian winter peas, crown vetch, sudangrass, sorghum-sudan hybrids, rapeseed, mustards, and cowpeas are effective for erosion protection.
• Pests and diseasesSome cover crops produce compounds that help fight soil-borne pests, while others are excellent at attracting beneficial insects. For example, crimson clover blooms to support beneficial insects, buckwheat supports large populations of beneficial insects and pollinators, and cereal rye reduces soil-borne diseases and root-knot nematodes.
• WeedsCover crops can suppress weeds by preventing seed germination, through competition, or by producing a chemical deterrent in the roots, called allelopathy. Hairy vetch, buckwheat, and daikon or forage radish reduce light penetration into soils, which suppresses weed seed germination. Dense-growing cover crops and those with aggressive root systems, such as peas, clovers, buckwheat, rye, and oats, manage weeds through competition. Buckwheat, brassicas, sorghum, sorghum–sudangrass hybrids, and subterranean clover produce allelopathic substances that inhibit weed growth.
• Nutrient managementCover crops can help to improve and manage nutrients in the soil. Cereal rye is excellent for nutrient cycling. Buckwheat and brassicas improve the availability of phosphorus in soils. Legumes, such as clover, vetch, and partridge pea, help cycle phosphorus in soils.

Cover Crops for Your Needs

When selecting cover crops for your garden, it is important to consider your specific needs and growing conditions. Some factors to consider include:

• TimelineSome cover crops are better suited to cooler growing seasons, while others thrive in the summer heat. For example, winter rye, wheat, and barley are commonly used as winter cover crops, while buckwheat, cowpea, soybean, sudangrass, sorghum-sudan hybrids, and hempseed are commonly used as summer cover crops.
• Growth rateSome cover crops are fast-growing and perfect for quick cover between other crops, while others are perennial, providing an excellent living mulch. Fast-growing cover crops include buckwheat, Berseem clover, Austrian winter pea, annual ryegrass, and oats. Perennial cover crops include medium red clover, crown vetch, and vernal alfalfa.
• Termination methodCover crops can be terminated by cutting, mowing, tilling, or using herbicides. The termination method you choose will depend on the cover crop you are using and your personal preferences. For example, low-growing cover crops like white, red, and Berseem clover can be terminated by tilling into the soil, while annual rye grass is commonly managed with tillage.
• RegionIt is important to select cover crops that are suitable for your region. Some cover crops are more winter-hardy than others, and some are better suited to warmer climates. American Meadows’ Cover Crop product pages include information on the ideal regions to grow each species as well as USDA hardiness information.

By carefully selecting cover crops for your home garden, you can reap the benefits of improved soil health and fertility, reduced pests and diseases, and increased yields.

Sources

• American Meadows: How to Select Cover Crops for the Home Garden: https://www.americanmeadows.com/content/grass-and-groundcover-seeds/how-to-select-cover-crops-for-the-home-garden
• University of Maryland Extension: Cover Crops for Gardens: https://extension.umd.edu/resource/cover-crops-gardens
• SARE: Building Soils for Better Crops: Cover Crops: https://www.sare.org/publications/building-soils-for-better-crops/cover-crops/

FAQs

What are cover crops?

Cover crops are plants that are grown to cover and protect the soil, typically between periods of regular crop production. They can be used to improve soil health, suppress weeds, reduce erosion, and provide habitat for beneficial insects.

What are the benefits of using cover crops?