Soybean agronomists in Northern Regions of the US and Ontario, Canada are promoting “ultra early” soybean planting. Recently, the soybean agronomist with the Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) recommended soybean planting mid-April in areas at the same latitude as Detroit, Michigan.

Among soybean farmers in Ohio, there is also interest in these early planting dates. However, planting early in Ohio comes at a risk of frost after emergence. (Northern areas, like Canada, tend to stay cool after planting. The soybeans do not emerge from the soil and are protected from freeze events. In areas like Ohio and Kentucky, early spring warm temperatures followed by freeze events can damage emerged soybean seedlings.) In our NCSRP-funded ‘Boots on the Ground’ trial, we’ve looked at planting dates on-farm over the past two years. In 2020, one of the cooperating farmers near Columbus planted soybean the first week of April. Then, there was a freeze event in May. His soybean stand was reduced, but he attributed the overall survival of his soybean plants due to the rye cover crop in his field offering
protection. (In other crops and in other states, “companion” cover crops have been used to protect winter-sensitive crops such as barley.) This project is designed to test the hypothesis that ultra early soybeans may be protected from freeze events by cover crop residue.

In our research trials, we’ve conducted several planting date studies, but have not had any planting dates in early or mid-April. However, due to information from surrounding states, we get many questions about this topic. This research will help answer a very common question from Ohio soybean farmers…How early is too early?

The objectives of this project are to: 1) Examine soybean yield in “ultra early” planting situations (early April) through more normal planting dates of late April through early June, 2) Examine the use of a winter rye cover crop to facilitate early soybean planting by removing soil moisture and protecting newly emerged soybean plants from adverse weather, and 3) disseminate results to Ohio soybean farmers through extension field days and winter meetings.

Results of this study will be discussed at field days and during winter meetings. A final report will be available to the public online at http://stepupsoy.osu.edu.

This project will directly support agronomic improvements that support Ohio soybean farmers’ commitment to conservation. Fall-planted cover crops have been associated with soil health improvements including increased water stable aggregation, increased biological activity, reduced soil erosion, and reduced nitrate leaching. Here, we will examine the use of a cover crop to facilitate early soybean planting, linking the conservation practice of cover crops to agronomic improvement of early planting that should increase soybean yield.

This project will also create value for Ohio soybean farmers by communicating with farmers and education of key target audiences.