By Linda Geist
Early planting remains strongly associated with soybean yield, according to research by University of Missouri state soybean farming system specialist Andre Reis.
“While late-season weather often influences final soybean yields, the potential yield is primarily set during planting, considering the ideal combination of planting date, variety (and its maturity group) and plant population,” he said. “Any stress the soybean crop encounters throughout the remaining growing season will either diminish or maintain the yield potential established during planting.”
With USDA predicting that farmers will plant 5% more soybean acres in 2026 due to projected higher prices, early planting might give growers an advantage. USDA also predicts an average of 53 bushels per acre in 2026.
In 2025, Missouri soybean farmers produced record yields, except on acres planted after May 17. Reis, who directs the MU Variety Testing Program, notes that nearly three decades of data confirms a consistent link between early planting and higher yields. These findings are consistent with results from private industry trials.
Each year, the Variety Testing Program evaluates more than 600 varieties of soybean, corn, wheat and grain sorghum at testing sites across the state. Reis and his team collected data from more than 5,200 plots in addition to analyzing more than 25,000 trials conducted by private seed brands.
Although many factors affect yield potential, Reis reiterates that planting date is the top predictor of yield. “The earlier, the better. Planting date is the main driver,” he says. It also gives the farmer flexibility and extends the planting window. “As important as increasing yield potential through early planting, finishing the planting season early prevents the steep yield declines associated with late planting dates.”
Soybean is more forgiving of cool temperatures than corn, so planting soybean first allows the farmer to wait to plant corn when it’s warmer.
Source : missouri.edu