Considerations Before You Plant

It’s April, so it’s not surprising we’ve all got planting on our minds. Some questions that we’ve gotten recently include seeding rate, soil nutrition and soil temperatures. Take a look at these topics as you get the planter tuned up.

Soybean Seed Rate

Brodbeck agronomists, Terry Jones and Denny Wickham worked together on this soybean planting rate chart. Note on the chart that seeding rates include an adjustment for 90 percent germ. The goal is to take advantage of growth habits of each maturity group and to ultimately achieve full canopy by R1-R2. After June 1, consider adding an additional 10 percent over the rate used in May. Increase the rate used in June by 18 percent for double crop following wheat.

 Potassium Soil Test Levels

A recent article by A&L Great Lakes Laboratories, indicated that soil test values for Potassium (K) have been generally decreasing over the past several years for the Eastern Corn Belt region. The average soil test readings have been showing a linear downtrend in K levels and increasing percentages of soil samples are showing declines in K levels.

The article states that there are likely several factors involved in the lower K values, but one of the primary reasons is higher yields of corn and soybeans. The higher yields lead to higher potassium removal rates that may not be accounted for in the fertilizer recommendations. K is a critical nutrient for achieving and maintaining high yields of both corn and soybeans so it is important to pay attention to crop removal rates and soil test levels and apply the necessary amount to maintain or increase K levels in the soil.

 Soil temperature

Corn germination or emergence can occur in as little as five to seven days if seed is planted into warm soils or can take up to four weeks if planted in soils at 50F or less. We recommend soil temperatures be at least 50F for two to three consecutive days (when taken in the morning at a depth of 1.5 inches) before planting.

Delayed germination and emergence can result in seed and seedling blights (mostly fungal diseases), seed rots, and chilling injury caused when unusually cold soil temperatures follow slow emergence. These conditions often result in thin stands and difficult replant decisions.

Give us a call with any questions or concerns on these or any other planting topics.

Terry, Dan, Rod and Denny