Cover Crops

A cover crop is a crop you grow for the benefit of the soil. They add organic matter to the soil and add nitrogen in a slow-release way. They can also be used as a mulch. Many types of plants can be used as cover crops – ryegrass, barley, wheat, and hairy vetch, to name just a few.

Use Penn State Extension’s extensive range of resources to further build your knowledge and expand your cover crop expertise. Topics covered in this section include managing soil quality with cover crops, as well as pest and disease management.

What Are Cover Crops?

Cover crops are plants such as legumes, grasses, brassicas, and buckwheat that are primarily used to slow erosion and improve soil health. However, there are many reasons why cover crops are grown. They also help control pests and diseases and smother weeds. Cover crops also help crop production by enhancing water availability.

They are often grown outside of the normal growing season, which in Pennsylvania is the six-month period from October to April.

Cover crops are grown to benefit the soil, rather than as a source of income; however, they can be harvested, which is a process called double-cropping. As such, it plays a vital role in farm business management – not only does it protect the soil over winter, but it also provides additional forage for cattle and livestock.

For more knowledge on cover crops, join Penn State Extension's Crops Days workshops and get updates on the latest agronomic research, products, and technology. These workshops will also get you pesticide applicator recertification credits.

Cover Crops Benefits

Cover crops are being used by an increasing number of agronomic crop producers. Eight US states, for example, more than doubled their cover crop acreage from 2012 to 2017. Here are some of the main benefits of cover crops.

Soil Health and Cover Crops

Cover crops’ primary role in agronomy is to slow erosion, enhance water availability, and improve soil health. They also increase biodiversity and bring many more benefits. Cover crop legume species, such as crimson clover or winter peas, will fix or capture nitrogen from the air and add it to the soil.

Producers have demonstrated success using cover crops to increase crop yields, improve soil fertility, add organic matter to the soil, break through a plow pan, and improve crop diversity.

There is also increasing evidence that cover crops are very beneficial in areas that experience erratic and increasingly intensive rainfall, as well as in areas that regularly experience drought conditions.

Weed and Pest Management With Cover Crops

Cover crops play an integral role in sustainable agronomic crop production. Not only do they help to slow erosion, and improve soil health and fertility, but they can also help with pest and weed management. In Pennsylvania, for example, aggressive cover crop species such as cereal rye and forage radish are being used. Because species such as these are so good at suppressing weeds, the need for herbicide application is often reduced.

How to Choose Cover Crops

Cover crop seed production is extremely regional; however, their benefits can be enjoyed nationwide. Cover crops have a host of benefits, but there’s not one single species that does it all, and there are lots of species and varieties to choose from. Careful choice of cover crop ultimately depends on individual agronomic producer’s goals.

Producers who want to be able to reap multiple benefits turn to cover crop mixtures. The success of a cover crop mixture depends on each species providing the desired services in balance with other species in the mix. Practicing agronomy professionals such as certified crop advisers, will be able to offer advice and suggestions on the best cover crops to use.