Early planting and good stands are the foundation of high double-crop soybean yields. Small grain harvest is very early this year. If we can get soybeans planted by the first week or two of June, there will be very little yield loss due to late planting. Good wheat and soybean yields plus high prices can make the wheat/soybean cropping system the most profitable in Virginia.
I stress that it is very important that we forge ahead with soybean planting. After mid-June, we lose about ½ bushel per acre per day with every day delay in planting.
This is not to say that double-crop yields will always be less than full-season yields. Rainfall during pod and seed development is most important. For two of the last three years, double-crop yields were equal to or greater than full-season yields. But, we can’t count on late-season rains every year. Therefore, it is important that we get the double-crop soybean set up for maximum yields. That means planting as soon as possible to maximize leaf area production.
For those of you that do not have adequate soil moisture, planting into dry soils is OK, but only if the soil is completely dry. If the soil has enough moisture to swell but not germinate the seed, the seed may die. If the soil has enough moisture to initiate germination, but not enough to send a root into soil moisture, it will definitely die. Considering the cost of seed, my suggestion is not to plant into these dry soils; wait for a rain. Only if you are sure that there is absolutely no soil moisture in the field and you have hundreds (or thousands) of acres to plant, would I suggest planting into dry soils. At $40 to 50 per bag, we don’t want to waste any seed.
Keep in mind that my seeding rate recommendation for double-crop soybeans is to plant enough seed to insure a final plant population of 180,000 plants per acre. Assuming 80% emergence, that’s 225,000 seed per acre (~75 lbs of seed). Do not attempt to lower seeding rates in double-crop settings. Furthermore, if planting moves into July, we’ll need to increase that seeding rate to 250,000 seed per acre. On droughty soils and July planting, yield increases will take place up to nearly 275,000 seed per acre.