The Sunbelt Expo farm has been the site of a test during the past two years featuring early maturing soybean varieties.

Early system soybeans have been adopted in the Mid-South but are rarely grown in the Southeast. The Expo test demonstrates that farmers may want to take a look at this cropping system.

With early system soybeans in south Georgia, indeterminate, Group IV bean varieties are planted in mid-April. Georgia Extension Agronomist Phil Jost says the critical moisture period for these soybeans occurs during July and early August. With the early varieties, soybeans are harvested during August and early September.

While this time frame coincides with the tropical storm season in the Southeast, timely harvest of early beans will allow the crop to escape dry weather during September and October that has hurt the yields of the determinate, Group VI, VII and VIII later-maturing varieties normally grown in the area.

In general, Jost says it is always a good idea to spread risk by using different planting dates and maturity groups when growing soybeans.

Jost notes that early maturing varieties tend to yield better when planted in close rows of 7 to 30 inches and at high seeding rates of 10 to 20 percent above normal. He says Georgia farmers growing early soybeans should plant between April 20 and May 31.

He notes that the system appears to have the most merit for productive soils in the middle and upper Coastal Plain and in the Limestone Valley regions of Georgia.

Retired University of Georgia Extension Agronomist John Woodruff helped to coordinate the early system soybean demonstration at the Expo farm.

“We’ve been growing early maturing soybean varieties at Expo because we believe they may yield better,” says Woodruff. He believes farmers can produce 65 to 70-bushel soybean yields by growing early varieties under irrigation. Woodruff also has tested upland rice at the Expo, but he says the early system soybeans show more profit potential.

“I’m excited about early system soybeans,” says Woodruff. “With irrigation, you can get 60 to 70-bushel yields consistently. You can’t do that regularly with the later maturing soybean varieties that farmers in the Southeast normally plant.”

Since the early system soybeans mature in late August, they normally escape damage from velvetbean caterpillars and farmers can eliminate spraying costs for this pest.

Jost concedes that early system soybean growers will probably need to treat their crop for stinkbugs. “These varieties really attract stinkbugs during early pod-fill in July,” adds Jost.

Woodruff is optimistic that soybean prices will strengthen. “I think we’ll see a comeback of soybeans in our region,” he notes. “As crude oil prices increase, I believe vegetable oil prices will go up. I believe we should focus on the potential for all oilseed crops with oil prices so high. Higher cost for petroleum products should eventually mean higher prices for vegetable oils.”

“If farmers can get $7 to $8 per bushel for soybeans, then they only need to get better yields, and early system soybeans offer good potential for higher yields.

Last year, Woodruff planted small plots of Group VI soybeans in close rows. He believes that close row or drill planting is important for getting the best yields from the early beans. The Expo test last year worked so well that the early system soybean test was increased to 10 acres this year. The 10-acre test was planted with 12 varieties on April 19, and results will be compared with yields from a Group VII variety planted in the same area.

Woodruff says Southern farmers in states such as Arkansas have maintained a viable soybean industry, in large part because they are growing the early maturing varieties for better yields and profits. “If we do it here in the Southeast, we’ll only be 20 years behind Arkansas,” he jokes. On a more serious note, he says, “With a $7 market and 70-bushel yields, the opportunity is there.”

Woodruff has seen 80-bushel yields grown with the Essex variety, a Group V soybean. Before he retired, Woodruff worked closely with grower Glenn Waller of Harrison, Ga. Woodruff says Waller has produced 64-bushel yields growing early system soybeans. During a year of severe drought on the Waller farm, early system soybeans produced 22 bushels per acre, compared to only eight bushels per acre for the full season varieties.

“Quality is the one drawback with early system soybeans,” says Woodruff. “Farmers must use timely harvest of these beans to maintain top quality.” Jost adds that harvesting should take place within 10 to 14 days after maturity to avoid shatter and seed quality problems.

Jost reports that early maturing varieties are also ideal for use as soybean trap crops. Planting these varieties around the edges of fields growing later maturing varieties can help in stinkbug control. The stinkbugs flock to the early varieties, and allow farmers to treat only those field edges with insecticides.