Introduction

Soybean seeding depth recommendations are at 0.75-1.25 inches for North Carolina, but the right planting depth will depend on field specific conditions at planting. There are circumstances where growers may plant deeper than that. Examples include planting to soil moisture with limited rainfall in the forecast or planting below a pre-emergence herbicide zone. However planting soybeans too deep can result in reduced stand and seedling vigor. This occurs because soybeans need to expend their energy reserves trying to get the seed out of the soil which can delay emergence. This lengthened time from planting to emergence can leave emerging plants more susceptible to damage from seedling diseases and insects. Deep planting can intensify stand loss when crusting occurs.

Symptoms

Symptoms include poor stand, delayed emergence, and reduced seedling vigor.

Management

Planters generally achieve more accurate and consistent depth than the use of a drill or air seeder. Regardless of planting equipment used, depth should be checked frequently to ensure desired depth is achieved, especially as soil conditions change throughout the field. If a grower must plant deeper than 1.25 inches for various reasons, the grower should consider using a variety with a larger soybean seed size because a larger seed has more energy to get the seed to emerge. The grower should also use a variety with a good seedling diseases resistance package in late planting situations.

Additional Resources

Soybean planting depth matters (MSU Extension)

Soybean Planting Depth Considerations for Iowa (Iowa State University Extension and Outreach)