SPRINGERTON, Ill. — Mike Plumer holds up a young tillage radish that already has a taproot approaching one foot long. Aboveground, the plant produces bushy leaf cover; but it’s below the ground where the tillage radish makes its significant mark, Plumer explained.

“Especially with soil that may include more clay than others, these radishes will bore into the ground, break up the soil and draw up nutrients that otherwise would be lost,” said Plumer, a retired natural resources educator and one of the Midwest’s authorities on cover crop use for the past 30 years.

On a recent brisk fall day, Plumer hosted a handful of farmers to one of his several test plots on Junior Upton’s farm in southeastern Illinois, an area known for its harder clay soil. Tillage radishes, while edible and consumed mostly in Asian countries, are gaining favorable ground as an excellent cover crop for farmers in between cash-crop seasons.

Less expensive ryegrass remains at the top of the list for Midwest farmers as a cover crop option, but others are equally fine choices as along as farmers have an effective management plan to handle the crop come spring, Plumer said.

“Over the years, we have seen huge benefits and huge returns with the use of cover crops,” he said. “Not all farmers need them, if they have a good rotation plan, but in many cases cover crops can make a big difference.”

Now a consultant with Conservation Agriculture, Plumer is entering what he calls his busiest time of the year. He has some 20 workshops scheduled throughout the Midwest during the next two months.

Successful cover crop management isn’t easy, Plumer explained, and on average it costs a farmer about $20-$40 per acre just in seed cost. But the benefits far outweigh the costs, particularly for no-till farmers.

Cover crops such as a variety of radishes, ryegrass, crimson clover, cereal rye, winter peas and hairy vetch tie up nutrients that otherwise would be leached from the soil. They build organic matter, loosen hardpan, suppress weeds and help prevent erosion, Plumer said.

No entity tracks the amount of cover crops planted each “off-season,” but Plumer said one large seed dealer told him last week sales of rye and crimson were up more than 400 percent this year, compared to last year.

Most cover crops should be in the ground by early to mid-September in the Midwest. For some farmers, that means planting immediately after harvest or overseeding a standing crop, Plumer said.

The workshop in Springerton was sponsored by Carbondale-based Food Works, a nonprofit dedicated to expanding the availability of local foods and helping local farmers.

Plumer’s next workshop is set for today and tomorrow, Dec. 7-8, in Decatur. Go to www.swcs.org for more information; to contact Plumer, call 618-364-2219.