Incorporating cover crops into a row crop rotation requires intentional consideration. What cover crop will you grow? When should you plant? And when do you terminate in the spring?  

A discussion was recently held on this topic during a meeting of the Agricultural Council of Arkansas on Aug. 15. 

The talk was led by Keith Scoggins, Arkansas Soil Health Specialist and Agronomist at the USDA-NRCS, and Bill Robertson, now an independent conservation agronomist who works with the Soil Health Institute in promoting soil health in Arkansas. 

Here are the top discussion points and best management practices for introducing cover crops to your row crop rotation.

1. Choose the right cover crop. 

 For farmers new to cover crops, cereal rye is a great place to start. Robertson said, “For me, straight cereal rye is the cover crop with training wheels, because it is easy to establish and easy to terminate.” 

However, he cautioned those determined to “plant green” – or plant into the cover crop without terminating it in the spring.  “You can’t let cereal rye get too big,” he said. “If you are bound and determined to plant green into cover crops, straight cereal rye is not the one to do it.” 

When selecting a cover crop mix, there are plenty of factors to consider. “Every farm, every field, every level of management is different,” Scoggins said.  

Related:Cover crops: How to boost biomass and soil organic carbon

“Chances are, you are not going to use the same cover crop mix across your soybean acres as you do corn acres. This is because of soil types, because of flooding, and because of your production.” 

2. Plant your covers in early fall.

Cover crops should be planted early enough in the fall to ensure crop establishment before winter. Robertson said if he had to circle one day on the calendar to plant covers it would be Sept. 15. This is especially true for straight cereal rye. 

“If you are going to plant cover crops, you need to have your seed ordered early,” Robertson said. 

Drilling the seed is the best way to ensure a stand, however planting cover crops lines up with cash crop harvest when labor is short. Running a drill might not be an option. In that case, Robertson said broadcasting, or sowing the seed is a good choice. He aims for 50 – 65 pounds of seed or about a bushel per acre. 

When broadcasting seed, the soil should be moist enough to ensure the germinated seedling can establish a root system to keep the plant alive. Robertson said, “I can fly seed out in front of a rain and get a good stand, as long as I can get the seed on the ground.” 

Cover crops should be planted early enough to ensure plant stands before winter rolls around. Conservation Agronomist, Bill Robertson said if he had to circle one day on the calendar to plant covers it would be Sept. 15. This is especially true for straight cereal rye. (Photo by Whitney Haigwood)

3. Plant cash crop seed deep enough to get a stand.

To ensure good seed-to-soil contact and stand establishment, your cash crop seed may need to be planted much deeper than when using conventional tillage methods. Robertson said this was his biggest challenge in learning cover crops, since that is nearly an inch deeper than cotton is normally planted. 

He also cautioned that cereal rye plant residue can “hairpin,” or become rope-like during planting. Watch for this on cloudy, misty days, because it impacts plant emergence. Robertson said, “You have to put enough down pressure and set the depth on the double-disk openers to cut through that residue in order to get a crop stand.” 

For fields that are on beds, Scoggins has seen good luck with broadcasting cover crop seed ahead of fall field preparation. This helps incorporate the seed and saves a planting pass across the field. “If you sow the seed in front of your listers or bedder rollers in the fall, it gets better incorporation.  

“You are going to make that fall prep pass anyway, so the only other pass you would need for sowing the cover crop would be a sprayer pass.” 

4. Put soybean acres in a cover crop rotation. 

Soybeans are a resilient cash crop to include in a cover crop rotation – more so than cotton or corn. Robertson has a passion for cotton, but he said, “Soybeans are so forgiving on cover crops. If you are using a straight cereal rye cover crop and you terminate late or have other issues they can handle it, soybeans are so easygoing.”  

From an Arkansas production standpoint, Scoggins noted that soybeans and rice are typically grown in a 1:1 rotation. He reported that approximately 3 million acres of soybeans and 1.5 million acres of rice are grown annually in the Natural State.  

“We would assume that half of those beans are not in a rice rotation, so we potentially have 1.5 million acres of soybeans that could easily be cover cropped,” Scoggins said. 

5. Know when to terminate the cover crop before spring planting. 

You can terminate cover crops or choose to plant green into the cover. Robertson said the ideal timeframe to terminate is the first week of April, when cereal rye is at late-boot. 

 “When that first head starts popping the boot on cereal rye, we have about a week to terminate,” Robertson said. “When it gets that far along, we have enough residue and soil cover through much of the season. We also don’t have a massive cover crop residue to worry about planting into.”  

If you plant green in cereal rye, prepare for a yield loss. Robertson said planting cotton into straight cereal rye green resulted in a 10 – 15% yield loss, according to his research. 

But no need to worry. Continue cover cropping and work on blends or strategies that fit your management to see a payoff down the road in input cuts for irrigation, pesticides, and fertilizer. 

6. Find a cover crop mentor.

Cover cropping is a conservation practice that is rocking agriculture. Get ready, because carbon amendments and relay cropping are on the agenda. It helps to have someone who is experienced. Find a mentor to guide you through the process of cover cropping.  

In Arkansas, you can reach out to the Arkansas Soil Health Alliance or the Soil Health Institute. You can also connect with Keith Scoggins by email at [email protected] or Bill Robertson at [email protected]. They will gladly guide you to a continuous living roots system to improve soil health on your acreage.