Grass-Legume Combinations

By Lynn Byczynski

Many farmers grow mixtures of cover crops to multiply the benefits of a planting. The most common approach is to grow legumes and grasses together. Some popular combinations include hairy vetch or red clover plus winter rye in cold winter areas or bell beans plus oats in milder winter areas. A legume-grass combination offers several benefits:

  • Legumes and grasses grown together balance the carbon-to-nitrogen ratio in the soil after plow-down. The legumes, rich in nitrogen, break down quickly while the carbon-rich grasses take longer to decompose. Growing the two together makes nitrogen available to help break down the grass residue and reduces the amount of time that must elapse before a subsequent crop can be planted.
  • A faster-growing crop such as oats or winter rye serves as a nurse crop to shelter less-robust, slower-growing plants such as red clover or sweet clover. Grasses establish quickly and prevent the growth of weeds that would otherwise compete with the legume.
  • Low-growing crops and taller crops planted together cover more of the soil and do a better job of preventing erosion and weeds. Sorghum grows tall, and cowpeas grow low; together they shade the soil and prevent weed seeds from germinating.
  • Legumes increase nutrient content of a hay crop that is to be used for livestock.
  • Combinations of cover crops reduce the risk of crop failure and allow for differences in conditions across a field. In spots where a legume doesn't establish well, the grass may do better and vice versa.

An Introduction to Cover Crop Species for Organic Farming Systems , from the eOrganic network.
Overview of Cover Crops and Green Manures , by ATTRA, the Sustainable Agriculture Information Service.

Lynn Byczynski is the editor of Growing for Market and the publisher of The Hoophouse Handbook.

Articles by Lynn Byczynski

About the author:

Lynn Byczynski was growing organic vegetables and cut flowers for market when she decided to create a magazine that would help market gardeners nationwide share experiences and information. Her first issue of Growing for Market appeared in January 1992 and it has been published continuously since then. GFM is renowned in the market gardening world for realistic articles that give growers practical, how-to information about growing and selling produce and flowers. Lynn is now partnering with Johnny's to provide similarly useful information for the website and other publications. Lynn, her husband Dan Nagengast, and their two children have grown vegetables and cut flowers since 1988, selling through a CSA, at farmers markets, to chefs, grocery stores, and florists. They currently grow cut flowers and hoophouse tomatoes on about 2 acres of their 20-acre farm near Lawrence, Kansas. Lynn is also the author of several books about market farming: The Flower Farmer: An Organic Grower's Guide to Raising and Selling Cut Flowers ; The Hoophouse Handbook ; Market Farming Success