But the right varieties and the right implement are still not quite enough to thoroughly control weeds.

“During the on-farm validation of effective cultivation regimes for weed control, it became clear that we needed to have uniform, almost perfect, stands of peanut plants to eliminate any gaps in the row where weeds could get a foothold,” Johnson said. “That’s where one of the SARE grants, led by Mark Boudreau, came into play.”

Boudreau, with UGA College of Agricultural and Environmental Sciences, coordinated research that identified the ideal combination of row spacing, row geometry, and seed spacing.

“The best system is peanut rows spaced 36 inches apart with six to eight uniformly spaced plants per foot of row,” Johnson said. “That eliminates gaps (skips) in the row where weeds can grow. We were able to demonstrate that production system on a large scale in an organic transition study led by Scott Tubbs.”

Tubbs, an assistant professor of crop physiology and management at the UGA campus in Tifton, received a SARE grant to study peanuts in an organic transitional system at three locations across Georgia, one of which was in Tifton.

“In those experiments at Tifton, the yields on two acres of organic peanuts averaged 5,211 pounds per acre in 2011. The 2011 state average was 3,400 pounds per acre,” Johnson said. “The results of the study showed that we can grow peanuts organically and it’s doable on a larger scale, not just small research plots.”

Johnson credits J. Frank McGill, a former UGA Cooperative Extension agent and retired UGA peanut specialist. Known as “Mr. Peanut.” McGill is considered one of the pioneers of modern peanut production in the South.

“Once we developed a rough prototype of an organic peanut production system, Frank and I were visiting a certified organic peanut farm in Screven County,” Johnson said. “Frank took one look at the planting, which looked impressive, and gave our team an enthusiastic thumbs-up. Coming from the pre-eminent expert in peanut production, I knew we were on the right track.”

Those research successes in organic peanut production have led to similar efforts on other specialty crops, like organic Vidalia sweet onion.

“The organic Vidalia sweet onion is a very high dollar, intensively managed crop. The production budget assumes weed control costs of $1,000 per acre, by hand,” Johnson said.

“We were able to control weeds using the tine cultivator on transplanted organic Vidalia onions for $25 or $30 an acre,” he added. “We tend to baby the Vidalia onion with extra inputs, like fungicides, but we were able to manage organic Vidalia onions without such inputs and produce yields comparable to state yield averages. “

Johnson and USDA-ARS research technician Dan Evarts were recently awarded the 2012 Land Stewardship Award from Georgia Organics for their research and outreach efforts in weed control strategies in organic peanut. While the award emphasizes contributions toward organic agriculture, the products from the research effort that work in organic production can also work in conventional systems, said Johnson.

“I find it very interesting that peanuts and Vidalia sweet onions are both intensively managed specialty crops and research on organic production systems for both crops points in the same direction,” Johnson said.

“Both crops can be successfully grown organically and the discoveries on organic production in both crops can be extended to conventional production systems and reduce costs of production.”

(Candace Pollack is the public relations coordinator for the Southern Region Sustainable Agriculture Research and Education program.)