Early planting gives you more time for more yield If time and equipment aren't an issue at planting, there's not much reason to plant soybeans early, says Jerry Mulliken. You might get a yield increase, but you can't count on it.
"If you've got plenty of labor and equipment to get done by the third week in May, there's no real reason to think about planting soybeans early," says Mulliken, a Nickerson, NE, farmer and consultant. "But if you're still going to be planting in June, it's something to think about."
It's a question of machinery management, according to Mulliken. "Planting soybeans early spreads out the work load. It helps you stretch what you've got further."
Farmers across the Midwest have found that higher yields from early planted beans also stretch their bin capacity. The beans that Mulliken no-tilled on Apr. 14 last year yielded 48 bu/acre compared to 42 bu/acre from beans he planted May 7.
University of Nebraska researcher Paul Jasa has seen similar results for a number of years in his research plots.
But you can plant too early, cautions Jasa. "March-planted beans have risks involved with late spring frosts and the potential for bean leaf beetle feeding," he says.
How early you plant may be determined in part by whether or not you no-till. Results from northwestern Missouri show that if you want to no-till, you need to pick well-drained fields where residue isn't heavy, according to Don Null, University of Missouri regional agronomy specialist.
"The soybeans we no-tilled on Mar. 28, 2000, yielded 36 bu/acre compared to 46 bu/acre in disked plots planted the same day," he says. "The highest soybean yield in both the no-till and disked plots came from those planted Apr. 12 (46 and 47 bu/acre, respectively).
"In this area, planting beans the second week of April would still be ahead of when most farmers start planting corn," Null says.
Southeastern Iowa farmer Cliff Neubauer has heard an earful about the risks of planting soybeans early. "We've had a lot of people tell us it would never work. But now some of those folks are planting early, too," he says.
"Others still say that sooner or later we'll have some beans killed by frost. But we've had to replant beans due to hail, drought and other risks. I think that frost is a minor one," says Neubauer, of Fairfield. "Also, you still have to use a little common sense. If the weather and ground conditions aren't right, you don't plant."
In 2000, Neubauer started drilling soybeans in 15" rows on Mar. 29 and had 200 acres in by the second week in April. "Our early planted beans were 10-15 bu/acre better than our others," he says.
The biggest risk with early planted soybeans isn't frost or seed diseases (as long as you use a fungicide), according to growers; it's insect damage.
"Our early planted soybeans attracted a lot of bean leaf beetles. There weren't enough to spray, but they certainly got our attention," says Nebraska's Mulliken.
The bean leaf beetle's real impact hit in late June, when Mulliken's fields showed signs of bean pod mottle virus. "It was a lot worse in the early planted beans. The beetles reached an economic threshold in the early beans and we ended up spraying them."
In spite of the damage, the early planted beans still outyielded Mulliken's regular beans. "We may spray fields earlier next year to see if we can stop the spread of the bean pod mottle virus," he says.