High yield late-planted soybeans
Normal soybean planting is down across the country, with just 68 percent of the nation’s bean crop planted. But growers still have time to maximize yields and revenue.
“Planting soybeans later than normal doesn’t necessarily have to result in low yields, if you think about the plant’s physiology and make a few adjustments,” says Jim Beuerlein, Ohio State University Extension agronomist.
Research has found that when planting is delayed, soybean maturity will only be one-third to one-half the delay in planting date. If planting is delayed by three weeks, as is becoming reality in many soybean states, plant maturity is delayed by only seven to 10 days. Pushing traditional planting timelines is not as costly as many growers imagine.
“I wouldn't give up on those 3.0 maturity beans yet,” says Agriculture.com Crop Talk member pupdaddy. “Last year those double crop beans I planted on July 7 were 3.1s, and with the late frost they matured well…Can't hope for that every year, but it does give you some idea of how late the maturity can go.”
Before switching to a shorter-season variety, Beuerlein suggests changing a few traditional planting practices.
The first thing he recommends is applying a fungicide treatment to the seeds prior to planting. Late-planted soybeans are often planted in below optimum soil conditions that support deadly soil-borne pathogens. A fungicide treatment will control seedling diseases and promote root structure and mass for the faster growing plant.
Growers planting on acres that were originally intended for corn and have received 100 plus pounds of nitrogen per acre need not bother with an inoculant. Beuerlein says the soybean plant will use the available nitrogen first, and continue to produce enough from residual bacteria in nodules. Fields not treated with nitrogen, however, may benefit from an inoculant.
“Some inoculants can be put on 90 days ahead of planting even with the powerful seed treatments with them,” says Crop Talk contributor hymark. “The polymer extenders are that good.”
Beuerlein also recommends helping the soybeans develop a complete leaf canopy that is the goal in normally planted soybeans. By planting narrower row widths, such as 7.5 inches to 15 inches apart, the late-planted soybean will have an easier time growing a complete canopy to collect as much sunlight as possible.
To fight the tendency of smaller plants with fewer nodes, Beuerlein suggests increasing the plant population so the total number of nodes per acre will be nearer to normal. He says that increasing the seedling rate will also help raise the height of the lower pods that will minimize what is lost at harvest.
“A 20 percent increase in seeding rate for late-planted soybeans should be adequate for most fields,” Beuerlein said.