Multi-Species Cover Crops

The benefits of single-species cover crops to water quality have been proven and promoted for many years. But are there economic, environmental and soil health benefits to planting multiple species of cover crops in the same field?

Cover crops are a leading best management practice for farmers. Farmers have been employing cover crops for several decades to recycle unused plant nutrients remaining in the soil from a preceding crop and help prevent erosion during the winter.

Maryland has long had a cost-share cover crop program to help incentivize farmers to use this practice. However, farmers mostly plant single species of cover crops, such as a cereal grain like barley or winter wheat, meant to sequester nitrogen.

A Hughes Center-funded study performed by Lindsay Thompson, formerly of the Maryland Association of Soil Conservation Districts, is finding that there are soil health, environmental and economic benefits to planting multiple species of cover crops in the same field.

For instance, one farmer participating in the study, John Bruning of Snow Hill, found that his sandy soil had marked improvements in soil organic matter after mixed cover crop plantings.

“When you plant multi-species compared to your monoculture cover corps, what I thought instantly is it’s like your dinner plate — If you’re having a steak, potato and salad, you don’t want all steak or all potato or all salad, you kind of want to mix it up,” Bruning said. “So when you do a multi-species blend, having a Brassica, a legume and say a cereal grain, you’re really maximizing the benefit of all three of those instead of planting just one.”

This project aimed to demonstrate the benefits of multi-species cover crop plantings to the Maryland Department of Agriculture. New this year, farmers may now plant multi-species cover crops as part of Maryland’s cover crop cost-share program. For farmers, cover crops sign-ups start July 1. For more information on that, visit mda.maryland.gov/resource_conservation/pages/cover_crop.aspx.

For more information on this Hughes Center-funded research project, please watch the video posted above. Results for this project will be made available after their official release on July 1.