Planting Considerations After Cold, Wet Weather Delays Planting

Planting Considerations After Cold, Wet Weather Delays Planting

By Nora Schultz, Sales Agronomist, CCA

Abnormally cold and wet weather has put a slight delay on planting this season in our part of the world. Before changing your current planting plan, consider the following.


  • For much of Iowa and Nebraska optimum planting window can reach all the way to May 10th. For eastern South Dakota that date is May 24th. Yields shouldn’t be impacted by planting date until 5-6 days after this window.
  • Wait to consider changing hybrid maturity until after you have reached that 5-6 day window after optimum planting date. That choice would be made around the 15th-20th of May for much of Iowa and Nebraska.
  • Avoid dropping your maturity by more than 5 days as it could bring in a hybrid that was not meant to be in your area, leading to reduced yields. For example, someone planting 111-108 should not go below 106-103 RM.


  • We suggest that you increase your soybean population if planting later than optimum planting date, roughly May 10th for most of Iowa and Nebraska.
  • Most soybeans planted in the Midwest are indeterminate plants, they continue to grow and flower at the same time. Soybeans are triggered to begin flowering due to changes in day length after the summer solstice, no matter how big they are.
  • This phenomenon means that later planted beans will be shorter and have fewer nodes to place flowers at that time than their earlier planted counterparts.  We compensate by having more plants in the field.
  • May 10th to May 20th – Increase population by 10-15%. For example, if you originally planned on planting 140,000 seeds/ac, raise your population to 155,000-160,000 seeds/ac.
  • May 20th to June 1 – Increase your population 15-18%. Example, if you’re originally planning on 140,000 seeds/ac, increase your population to 160,000-175,000 seeds/ac.
  • Consider switching soybean maturity after June 10th.