7 Tips for a Successful Soybean Double-Crop

Double-crop soybeans can potentially be some of a farm’s most profitable acres. Follow these tips to make the most of your double-crop.

1. Optimize Your Wheat Harvest for Double-Crop Planting.
   Consider harvesting wheat at 18% to 20% moisture and artificially drying the grain to allow for earlier double-crop planting. This should help maximize your wheat and double-crop soybean yields while maintaining grain quality.
   
   Make combine adjustments to maintain soil moisture for double-crop beans and to decrease residue that can harm seed/soil contact during bean planting.
   • Try harvesting in different directions to find the angle at which the header best picks up the wheat.
   • Adjust the reel slightly ahead of the cutter bar and far enough down to lay the head on the platform.
   • The reel should turn slightly faster than ground speed.
2. Prepare for Weeds By Selecting the Right Variety.
   Weed pressure can be significant in double-crop soybeans. Select seeds that will allow for effective herbicide treatments, such as the Enlist E3^® soybean trait with tolerance to 2,4-D choline, glyphosate and glufosinate.
3. Follow Some of Your Full-Season Planting Practices.
   Use the same practices that you would for full-season beans when it comes to soil moisture and soil conditions to achieve timely germination.
   
   Plant at 1”-1.5” depth for ideal emergence time.
4. Increase Your Seeding Rate.
   Double-crop soybeans require higher seeding rates because they are destined to be shorter and produce fewer pods per plant. Higher seeding rates enhance plant and pod height to compensate, and they counteract the effects of any high wheat residue in your field.
   • Increase seeding rate by 5-10% to achieve optimal stand.
   • Seeding rate = Targeted final stand/(%germination x % emergence)
   • Aim for 130,000-140,000 stand count for full season beans.
   • Target 140,000+ stand count for double-crop beans.
   • If planting 7.5-inch rows using a drill, aim for 160,000+.
   Higher rates also enable quicker canopy closure, which can be a benefit in drought- and/or heat-prone environments and can slow down or inhibit weed emergence and early growth.
5. Consider Decreasing Row Spacing.
   Narrower row spacing is likely to provide a greater yield benefit in double-crop beans, when soybeans have limited time for vegetative growth before flowering. Consider planting 15-inch rows, which some research suggests produces a 4 bu/acre yield advantage of over 30-inch rows.
   
   Watch out for moisture stress, brown stem rot, white mold, nitrogen stress and soybean cyst nematode. These threats are more common in narrow row spacing and can reduce or erase yield advantage.
6. Evaluate Stand Counts Promptly.
   Heavy residue in a double-crop field can cause hairpinning and poor emergence of soybeans. Evaluate stand count upon emergence to determine whether you’ll have a good crop.
   
   Count the stands inside a 30-inch hoop and multiply the number by 8,878 to determine field population. Take stand counts in multiple spots throughout the field.
7. Scout Early and Often for Pests and Diseases.
   Smaller crops are more vulnerable to pests, making scouting very important in double-crops. Pests to watch for in late-planted beans include:
   • Defoliating insects like bean leaf beetles, Japanese beetles, Mexican bean beetles, and a variety of caterpillars
   • Soybean aphids
   • Stink bugs
   • Soybean podworm – corn earworm
   Keep an eye out for these common diseases in double-crop beans:
   • Rhizoctonia solani
   • Phytophthora root and stem rot
   • Cercospora leaf blight and seed stain
   • Frogeye leaf spot
   • Viruses

   See symptoms and treatment thresholds for insect and disease threats.