Planting soybeans early continues to gain in popularity due to the yield-boosting potential of faster canopy closure, increased plant nodes, higher pod retention and more. However, risks do exist. Though early-planted soybeans face an extended plant-to-emergence period due to cold temperatures, you can take measures to help your seeds withstand the challenge.
We’ve put together an overview of the threats that can undermine early-planted soybean crops and some tips on managing them effectively so you can reap the benefits of getting your beans in the ground early.
Risks of planting soybeans early
Planting soybeans early can increase risk for certain diseases and expose seeds and young seedlings to cold soil temperatures, leading to injury and even death.
Increased risk of soil-borne pathogens
Soilborne soybean seedling diseases prosper in the cold, water-saturated soils common early in the season. These soil conditions cause critical delays between germination and emergence, significantly reducing emergence rates and leaving soybean seeds vulnerable to soilborne diseases.¹
Cold soil risks when planting soybeans early
If the soil temperature is below 50 F during the first 24 hours after planting, soybeans are at high risk of imbibitional chilling injury as the soybean seed imbibes (rapidly takes up water from the soil).²
Soil temperatures around 40 F can make soybean seeds fail to germinate entirely or cause seedling death.³
Cultural practices can impact soil warming. For example, heavy crop residue can slow down warming, especially when left on the soil surface in a no-till system. However, Iowa State University researchers have found mixed results when removing residue from the row for very early planting. Research showed that on one hand, residue removal warmed soil sooner, promoting earlier germination and emergence. But on the other hand, when residue is removed, newly emerged plants are more exposed to the elements, such as frost.⁴
Risk of early frost on soybeans
The earlier soybeans are planted, the more likely late spring frosts could cause injury or death to seedlings.
Because the growing point of soybean seedlings is above ground as soon as they emerge, crops are especially vulnerable to frost damage. Frost damage to soybeans may appear as blackened or withered plants within a day after frost occurs; however, it takes about 3 to 5 days for soybean plants to show whether they will recover or not, so wait to make your official assessment of the damage.
How to manage the risks of early-planting soybeans
Following an early soybean planting checklist can help ensure your crop has the best chance at survival.
Here are some general guidelines to help your early-planted soybeans not only survive, but thrive:
- Plant when soil temperatures are above 50 F.
- Be aware of your early plant dates for insurance coverage of replants
- Use high-quality seed varieties with good early-season vigor or cold tolerance. Seed treated with disease protection using Obvius ® Plus is a must for early planting.
- Increase seeding rate to compensate for 10% to 20% expected reduction in germination rate when planting early. Early planted fields may still be less uniform across the field.⁵
- Monitor weather forecasts, learn the predicted conservative last frost dates in your county and use historical weather records to help you arrive at a usable planting date.
- Choose disease-resistant seed varieties that can mitigate risk associated with diseases like soybean sudden death syndrome and Phytophthora. Using ILEVO® seed treatment can protect form sudden death syndrome.
- Select fungicides that are effective against Fusarium, Pythium, Phytophthora and Rhizoctonia.
Experts are available to help you make your decisions. Reach out to your seed retailer, a nearby extension office agent, or a seed company professional like your regional BASF representative.
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Endnotes
- Kruger, Greg, et al. “Factors Influencing Cold Stress in Corn and Soybean.” CropWatch, cropwatch.unl.edu/factors-influencing-cold-stress-corn-and-soybean/. Accessed 18 Jan. 2025.
- Lindsey, Laura, and Alexander Lindsey. “Cold Weather Impact on Corn and Soybean.” Ohio State University Extension, Nov. 2021, agcrops.osu.edu/newsletter/corn-newsletter/11-2021/cold-weather-impact-corn-and-soybean. Accessed 18 Jan. 2025.
- Kruger, et al. “Factors Influencing Cold Stress in Corn and Soybean.”
- Licht, Mark. “Mitigating the Risks of Very Early Soybean Planting.” Integrated Crop Management, Iowa State University, 14 Apr. 2020, crops.extension.iastate.edu/blog/mark-licht/mitigating-risks-very-early-soybean-planting. Accessed 18 Jan. 2025.
- Licht. “Mitigating the Risks of Very Early Soybean Planting.”
