Cover Crops: A Cornerstone of Sustainable Farming

Charlotte Renner

By Charlotte Renner

When farmers plant crops for harvest, sometimes the soil they grow on can pay the price. That’s why it’s environmentally responsible to utilize cover crops. 

Sohat is a cover crop? It’s a plant that helps keep soil healthy by slowing erosion and heaving, smothering weeds, controlling pests and keeping the soil in place.

A vast majority of our Known & Grown (K&G) farmers use cover crops on their farms. Utilizing cover crops is actually one of the practices Missouri Coalition for the Environment (MCE) looks for when recruiting new farms to the K&G program. 

One of the main reasons for this is that cover crops protect the soil beneath them, according to MCE’s K&G specialist Chris Wimmer. “Nothing good happens when the soil is bare,” Wimmer said. “When the soil is bare, the wind can blow the topsoil away. Rainwater can erode the topsoil. Weeds can get a foothold.”

Wimmer said some of the most popular cover crops for Missouri farmers are rye and vetch. Rye grows deep roots which allow it to hold soil in place. This helps fortify the soil against winter weather and erosion. After the deep roots die and decompose, it adds tons of nutrients back into the soil. Vetch also benefits soil nutrients. It is actually a legume that “fixes” nitrogen. This means it converts the nitrogen in the air into nitrogen in the soil that plants can use. Without using a cover crop like this, farmers would have to supplement their soil with fertilizer containing nitrogen.

“If there’s one thing that’s most important for plant growth, nitrogen is the top thing,” Wimmer said. “Nitrogen is what encourages green growth and accelerated photosynthesis.”

Using cover crops like these can also increase biodiversity and attract pollinators to farms. Wimmer said they grow as quickly as weeds, but they actually help the plants around them. 

“From the time you planted in October to the time you smoosh it down to plant tomatoes or whatever at the end of April, early May, that stuff could be six feet tall,” Wimmer said. “And I’m always impressed when I go in there to kill mine down. It is just loaded with ladybugs, lacewings…it is just a habitat for beneficial insects.”

According to SARE’s, farmers will see a 3 to 5% increase in crop yield over a 5 year period when they use cover crops.

For more information on our Known & Grown farms who use cover crops, visit knownandgrownstl.org. You can also visit MCE’s website for more information on food and farm at moenvironment.org.