Double-crop soybeans and soybean system is a profitable way for U.S. farmers to get two crops from the same field in one year. While this practice increases total farm output and improves soil health, it comes with significant risks, including the limited growing season and reliance on timely rainfall. Success hinges on a set of critical best practices that maximize yield for both crops while minimizing potential for crop failure.
Economics: Increasing Farm Output and Profitability
The primary economic driver of double-cropping is the opportunity to generate additional income from a second crop. While soybeans planted after wheat typically yield 10-15% less than a full-season soybean crop, the revenue from the second crop often makes the system more profitable on a per-acre basis than growing either crop alone.
- Increased Net Income: The combined net income from both the wheat and the double-cropped soybeans is usually higher than a single full-season soybean or corn crop. This is because farmers can spread fixed costs, such as land rent and machinery expenses, over two revenue streams.
- Cash Flow Management: The wheat harvest in late spring/early summer provides an early cash injection, which can help with cash flow and cover input costs for the second soybean crop.
- Efficiency: A double-crop system allows for more intensive use of farm equipment, labor, and capital throughout the year, improving overall operational efficiency.
- Soil Health Benefits: Integrating a winter wheat crop into the rotation improves soil structure, conserves moisture, and reduces erosion, which can lead to long-term yield benefits and reduced input costs for subsequent crops.
Risks: The Challenges of a Shortened Season
Despite the economic benefits, double-cropping is a high-risk venture that demands precise management. The risks are tied to the compressed timeframe and dependence on weather.
- Late Planting and Shortened Season: The biggest challenge is the tight turnaround. Double-Crop soybeans must be planted immediately after the wheat harvest, which is typically in late June or early July. This leaves a shortened vegetative growth period for the soybeans before they begin to flower, which can limit their yield potential.
- Moisture Stress: Soil moisture is the single most critical factor for success. If the ground is too dry at the time of planting, the soybean seeds may not germinate, or emergence may be delayed, wasting valuable growing time. A drought in July or August can be catastrophic, leading to a complete crop failure.
- Herbicide Carryover: Herbicides used on the wheat crop must be carefully selected to avoid carryover issues that could damage or kill the following soybean crop.
- Increased Pest and Disease Pressure: The practice of no-till planting into wheat stubble can increase the risk of certain diseases and pests, making proactive scouting and management essential.
Best Practices: A Playbook for Success
To mitigate risks and maximize profitability, farmers must follow a strict set of best management practices.
- Plant Early, Plant Fast: This is non-negotiable. The goal is to plant soybeans within 24-48 hours of wheat harvest. Some farmers even harvest their wheat at a higher moisture content (18-20%) and dry the grain, to gain a few crucial days for earlier soybean planting.
- No-Till is King: Planting soybeans directly into wheat stubble with a no-till drill is the preferred method. This practice conserves vital soil moisture and reduces soil erosion, which is crucial for a crop planted in the heat of summer.
- Increase Seeding Rates: To compensate for the shorter growing season, farmers should increase their seeding rate by 15-30% over a full-season crop. A higher population density will help the plants form a canopy faster, which is key for suppressing weeds and retaining moisture.
- Use Narrow Rows: Narrow row spacing (7.5- to 15-inch) allows for quicker canopy closure, which helps with weed suppression and improves light interception.
- Select the Right Variety: Variety selection is critical. Farmers should choose a soybean variety that is one-half to one maturity group earlier than their full-season varieties. This ensures the crop can reach maturity before the first fall frost, but without sacrificing too much vegetative growth.
- Manage Residue: The wheat residue is a double-edged sword. While it’s great for moisture retention, excessive residue can interfere with the planter, leading to poor seed-to-soil contact. Uniformly spreading the residue with a chopper or shredder can improve planting efficiency.
- Scout Aggressively: The compacted growing season and potential stress from heat and moisture make the double-crop soybean plant more vulnerable to insects and diseases. Timely scouting and intervention are vital to protect the crop’s yield potential.
