Growers who still have soybeans to plant can make some changes to help increase yields in late-planted fields. Ohio, Indiana, North Dakota and South Dakota reportedly have some soybean to plant.
“The goal of normally planted soybeans is to develop a complete leaf canopy that collects as much sunlight as possible by the time flowering begins,” reports Jim Beuerlein, Ohio State University professor emeritus and technical advisor to Becker Underwood. “To duplicate this condition in late-planted soybeans requires using narrower row widths, such as 7½ in. apart or no wider than 15 in. apart, which will help late-planted soybeans produce a better canopy.”
Soybeans planted later in the season also tend to result in smaller plants with fewer nodes, Beuerlein explains. Therefore, it’s important to establish higher plant populations so the total number of nodes per acre will be nearer to normal. “A 20% increase in seeding rate for late-planted soybeans should be adequate for most fields,” he recommends. “Increasing the seeding rate can also help raise the height of the lower pods to minimize the number of pods lost at harvest.”
Research has shown that when planting is delayed by three weeks, plant maturity is delayed by only seven to 10 days, so it may not be necessary to switch to a shorter-season variety, Beuerlein says.
Late-planted soybeans often are planted in less-than-optimum soil conditions – conditions that tend to support the presence and virulence of soilborne pathogens. Applying a fungicide treatment to soybean seed prior to planting will help control seedling diseases and increase root structure and mass to support a faster-growing plant.
For producers who end up planting soybeans on acres that were originally intended to be planted to corn and have already received 100 or more pounds of nitrogen per acre, Beuerlein says applying an inoculant is probably not necessary. However, for fields where nitrogen hasn’t been applied, the use of an inoculant is still a best-management practice for optimizing yield potential and profitability.