Corn planting jumps in past week
But rains expected to halt planting again.

Linda Geist
Senior Information Specialist
University of Missouri Cooperative Media Group

May 06, 2015

COLUMBIA, Mo. - Missouri farmers can plant a lot of corn quickly when fields are dry.

In one week, corn planting in the state jumped from 20 percent complete to 61 percent complete, according to the USDA's May 4 crop progress report. That puts corn planting ahead of the state's five-year average, University of Missouri Extension specialist Bill Wiebold said at a May 5 teleconference.

But corn planting likely comes to a halt this week.

Pat Guinan, climatologist for MU Extension's Commercial Agriculture Program, said significant amounts of rain are in the forecast for the central U.S. over the next week.

May typically is Missouri's wettest month, but the next seven days are expected to be "unusually wet," Guinan said.

Parts of the state are dry and could stand to see some rain, he said. Heaviest rains this month have affected northwestern Missouri, where more than 2 inches have fallen. Localized flooding was reported on May 4, pushing river tributaries to their banks in some areas. Two inches of rain fell in less than an hour in the St. Joseph area. And more is on the way.

Unseasonably high temperatures kicked off the month. "I think that we've gone from April to June in one week," he says.

Guinan said temperatures should return to May averages by next week.

Cool, rainy weather pushed corn planting in Missouri's Bootheel a "good month behind," said MU Extension specialist David Reinbott.

"We can go from 'I wish it rain' to 'I wish it would stop raining' quickly," Wiebold says.

MU Extension specialist Todd Lorenz said some mid-Missouri farmers are replanting due to "curling" of corn. This happens when corn is planted too deeply in cool soil in an effort to find moisture for emergence.

How deep is too deep? It depends, Wiebold says.

Variables such as moisture and soil type matter, but, overall, Wiebold recommends planting no more than 2 inches deep. At 3 inches, it's harder for the corn's mesocotyl to extend and emerge.

Cool soils and cold rains can damage the seed membrane and result in imbibition. Lower germination, delayed seedling growth, poor nutrient uptake, soil disease and pest entry can follow.

"The worst scenario is to plant and then to get cold rain," he says. Planting in cold, wet soil also increases compaction and results in root systems that can't withstand hot, dry summer days.

Look at soil temperatures and conditions, not the calendar, when deciding on planting date, Wiebold says. Patience improves yields.

Source: William Wiebold, 573-673-4128 (cell); 573-882-0621