Rye lessons learned here at The Rodale Institute
We describe our own variation on planting soybeans into a rye cover. Hint: it involves a roller.

By Matthew Ryan, ag researcher at The Rodale Institute, which publishes NewFarm.org

Rollin' in my sweet baby's rye: Planting soybeans no-till into rye using a homemade front mounted roller.

September 12, 2003: Researchers at The Rodale Institute have been experimenting with using rye as a cover crop for organic soybeans for a number of years now. One of the treatments we were especially pleased with was no-till planting soybeans into a rolled-down rye cover crop. The idea is to grow a good thick stand of rye planted in October; then once the rye has reached the heading-out stage, you roll over it to mechanically kill it and plant soybeans directly into the weed-suppressing mulch.

As with any mechanical killing of a cover crop, growth stage is very important. In order to effectively kill the rye you should wait until it is fully heading out, which is usually sometime in mid May to early June for us in Pennsylvania. We now use a front-mounted roller for our mechanical killing, but we have used other pieces of equipment in the past such as cornstalk choppers and culti-packers. The front-mounted roller is designed with unsharpened blades welded to a hollow cylinder drum that can be filled with water for additional weight. (More details on this roller will be coming in the near future, as will details of our less than successful experiences with hairy vetch as a weed-suppressing cover crop.)

In order to be able to plant into the thick rye residue you need to use a planter with a double disc opener. We tried for a couple of years with a planter rigged with a shoe opener, but this dragged the cover crop residue and resulted in poor seed placement. The Monosem air-planter that we use actually has a series of devices to allow for proper seed placement. First rolling trash openers (similar to the discs on a rotary hoe) pull some of the rye away to allow for a bubble coulter to slice into the soil. Next a double disc opener spreads the soil and a seed is dropped in and pushed firmly into place with a plastic device.

One of the tricks we have learned is that you should plan ahead and try to plant your rye cover crop perpendicular to the direction you want to plant your soybeans. This helps to completely cover the ground when you roll the following spring. If you plant your cover crop in the same direction as the soybeans, you are liable to have 7” gaps in your rye mulch mat once it is rolled, allowing light to penetrate and consequently more weeds to break through.

Matthew Ryan has worked at many levels of research and farmer outreach at The Institute, and co-designed TRI's multi-factor cover crop and reduced tillage trials. Ryan also designed the Institute's compost tea verification study funded by USDA-SARE.