Evaluating the pros and cons of winter cover crops for your corn and soybean fields? Here’s a list of popular midwest cover crop options to help you determine which ones match up best with your conditions, location, goals and timing requirements.
Corn cover crop options
There are two categories of common winter cover crops for corn acres: winter-kill species and winter-hardy grains.
Winter-kill corn cover crops
Broadleaves: This category of cover crop includes brassicas, oats, sorghum-sudan grass, and field peas. They have a low C:N ratio (< 20), decomposing quickly when naturally terminated by freezing temperatures, and rereleasing nitrogen rather than immobilizing it in the plant or microbes.¹ Drawbacks include lower biomass and the potential for residual herbicide to kill or stunt cover crop growth.
Oats: These plants function similarly to broadleaves with two exceptions. Oats are easier to establish but more difficult to seed aerially.
Winter-hardy grain corn cover crops
Cover crops in this category include cereal rye, wheat, triticale and others. Winter-hardy crops can help manage weeds, reduce soil compaction and provide food for microbes while uptaking residual nitrogen.
Cereal rye is often used for erosion control, forages, improved soil health and weed control. It’s typically a good fit before corn and after soybeans, since soybeans are often planted later than corn, giving rye more time to introduce organic matter into the fields before termination.
Drawbacks include a high C:N ratio (if not terminated early) and the potential to tie up some nitrogen, which can be detrimental to growing corn. They can also increase the risk of harm from sources like Pythium.²
Another downside is the time and labor required to terminate winter-hardy cover crops.
Soybean cover crop options
Unlike the options you face when choosing a corn cover crop, there is only one category of recommended winter cover crops to plant before soybeans: winter-hardy grains. Among options like wheat and triticale, cereal rye is a popular choice due to its consistent ability to grow excellent roots, build soil composition and scavenge excess nutrients.
Cover crop resources
Resources are available to help growers discover which of the many cover crop options might work best for their circumstances.
USDA’s Cover Crop Chart includes information on 70 cover crop species, with details about their growth cycle, relative water use, plant architecture, seeding depth, forage quality, pollination characteristics and nutrient cycling.
Midwest Cover Crops Council offers their Cover Crop Decision Tools, a robust online resource that offers expert cover crop information and recommendations based on growers’ specific goals and is keyed to their specific location, down to the county level.
Cover crop choices and timing decisions can be highly variable based on many different factors. If in doubt, have a conversation about your specific operation and goals with your local ag retailer or university extension agent.
Experts are available to help you make your decisions. Reach out to your seed retailer, a nearby extension office agent or a seed company professional like your regional BASF representative.
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Endnotes
- “Carbon: Nitrogen Ration(C:N).” Natural Resources Conservation Service, USDA, Sept. 2022, www.nrcs.usda.gov/sites/default/files/2022-09/SoilTechNote23A.pdf. Accessed 4 Aug. 2026.
- Lechuga, Rachel. “The Impact of Disease Management and Cover Crops on Corn Yields: Research Highlights from Dr. Alison Robertson.” Illinois Sustainable Ag Partnership, 20 Aug. 2024, ilsustainableag.org/the-impact-of-disease-management-and-cover-crops-on-corn-yields-research-highlights-from-dr-alison-robertson/. Accessed 4 Aug. 2026.
