Cover Crops
Cover Crops for Organic Production: Building Soil and Boosting Resilience
In organic agriculture, the soil is more than a medium for plant roots—it's a living system that forms the foundation of healthy crop production. One of the most effective tools organic growers can use to enhance that foundation is the cover crop. From fixing nitrogen to improving water infiltration and reducing erosion, cover crops offer a broad range of benefits that align perfectly with organic farming principles.
Cover crops, sometimes referred to as green manures, are plants grown primarily to improve soil health rather than for harvest. Depending on the species, they may fix nitrogen, scavenge nutrients, suppress weeds, break up compacted soil, or increase organic matter. Selecting the right cover crop depends on the farmer's goals, the season and thinking ahead to terminating the crop.
Growers looking to dive deeper into cover crop selection can explore the Cover Crop Type Information Document, which helps match species to farm needs. The Soil Building Cover Crops guide, Building Soils for Better Crops - SARE from SARE Northeast also outlines species performance based on season, region, and function. Cover Crops for Sustainable Crop Rotations to improve soil and farm management from SARE can provide valuable information. The 2017 National Conference on Cover Crops and Soil Health is available online from SARE.
For new and transitioning organic farmers, cover crops can feel like an investment that doesn’t yield immediate results. However, long-term studies have consistently shown improvements in soil health, yield stability, and resilience to weather extremes. The Overview of Cover Crops and Green Manures from ATTRA provides a thorough introduction to how cover crops fit into organic production systems using ATTRA’s five soil principles: reducing disturbance, keeping the soil covered, maintaining living roots year-round, increasing diversity, and incorporating livestock grazing.
One area gaining momentum is the integration of cover crops with livestock through managed grazing. The Miller Farm Case Study demonstrates how strategically grazing cover crops can accelerate soil restoration and improve forage quality. Farmers interested in dual-purpose systems should explore Pasture Cropping: Planting Summer Cover Crops in Cool-Season Perennial Pastures.
Cover crops also play a key role in reducing the need for tillage in organic systems—an ongoing challenge given weed management pressures without herbicides. The ATTRA guide on Reducing Tillage Intensity in Organic Production outlines how cover crops contribute to soil structure and fertility while reducing soil disturbance.
Beyond their physical impacts on the soil, cover crops can influence microbial activity and overall soil biology. In the ATTRA publication Cover Crops, Green Manures, Pre- and Probiotics: Soil Amendments, Fertilizers, or Both?, researchers explore how cover crops support microbial communities that are essential for nutrient cycling and disease suppression.
Farmers interested in the broader impacts of cover cropping can tune into ATTRA’s podcast episode 243, which discusses how these practices affect both soil health and crop productivity.
For more in-depth training and region-specific recommendations, SARE’s Northeast Cover Crop Resources and the ATTRA Cover Crop Topics Page offer research-based tools and practical tips to help farmers design systems that are regenerative, resilient, and rooted in healthy soil.
More reading and information are available at:
Cover Crops | Maine Organic Farmers and Gardeners
Three Legume Cover Crops for Nitrogen, Better Tilth and More - NOFA/Mass