Carrie Knott, University of Kentucky grain crops specialist, recently shared information for maximizing soybean yields as producers prepare to begin planting. She noted that in order to make the most of the opportunity, soybean producers need to think about planting in early May, specifically in Western Kentucky. For producers working in Central Kentucky, Mid-May is the ideal target, according to Knott.
“Soil temperatures 2 inches below the ground need to reach and sustain at least 50 degrees F, and there needs to be no risk for a killing freeze,” she says.
Some producers were able to plant earlier in the state as a result of a warm March. Soil temperatures reached 50 degrees Fahrenheit at the end of the month, but this came before the last killing freeze date for most of the region. On April 15, temperatures fell into the low to mid-20s in Kentucky, plunging soil temperatures to 40 degrees Fahrenheit. Now, Knott suggests that producers assess their crop for freeze damage if they planted early.
“If soybeans were still below the ground on that date, their chances for survival are good, but if they were above ground on April 15, damage may have likely occurred,” says Knott.
The ideal time to plant soybeans is when ground temperatures are between 50- and 60-degrees Fahrenheit, according to Knott. She recommends increasing seeding rates to offset higher stand losses if producers choose to plant early.
“They may also want to select seed that is treated with a fungicide and insecticide, as cool, wet conditions typical of this time of the year slow germination and plant growth,” says Knott. “This increases the risk for seedling diseases and insect damage to young plants.”
Additional planting information can be found by contacting a local office of the UK Cooperative Extension Service.