The first winterhardy, early flowering vetch variety for the northern U.S. has been released by the USDA-Agricultural Research Service (ARS). Vetch is a cover crop and weed-suppressing mulch favored particularly by organic farmers.

But conventional farmers are also interested because the nitrogen-producing plant’s mulch can lower their nitrogen fertilizer expenses by a third to a half and reduce pesticide loss in runoff.

Called Purple Bounty, the variety was developed by USDA-ARS geneticist and breeder Thomas Devine and collaborators.

Until now, hairy vetch had limited use north of Maryland because it copes poorly with northern winters. But Purple Bounty has survived winters as far north as upstate New York.

Devine, with the ARS Sustainable Agricultural Systems Laboratory in Beltsville, MD, spent nine years breeding the variety, using traditional breeding methods so it would be acceptable to organic farmers. He started with several hairy vetch types from Auburn University, Auburn, AL, and from the U.S. National Plant Germplasm System. There he found early flowering types.

From these, Devine selected for improved winterhardiness while maintaining early flowering. He harvested seed from plants that survived winters at Beltsville and at the University of Maryland farm at Keedysville in northern Maryland. Purple Bounty emerged from nine cycles of selection, with the right blend of winterhardiness and early flowering.

It flowers two weeks earlier than a commonly used variety. This allows farmers to plant their main crops earlier in spring and use corn and tomato varieties that require a longer growing season.

Limited quantities of seed should be available for planting in 2008, with commercial quantities available in 2009.

Devine's collaborators on the release of Purple Bounty included the Rodale Institute near Kutztown, PA; the Cornell University Agricultural Experiment Station at Ithaca, NY; and the Pennsylvania Agricultural Experiment Station at University Park.

Read more about the research in the April issue of Agricultural Research magazine.