Like the start of a big race, or the beginning of a championship game, farmers in Minnesota and Iowa are eagerly awaiting the initiation of full-scale field work. Very cool temperatures and moist soil conditions have existed across the region during most of the month of April, resulting in cold soil temperatures and soil conditions which have not been conducive to the initiation of corn planting in Minnesota and Iowa. A few farm operators have planted some peas and small grain crops in isolated locations in recent days; however, in most areas, soil conditions have remained too cold and wet to begin full-scale spring fieldwork.
At the U of M Research and Outreach Center at Waseca, Minn., the average soil temperature on April 24 was only 32° F at the 2-in. and 4-in. level, which is far too cold for good corn planting conditions. The top few inches of soil did warm up considerably this past weekend with some above average temperatures; however, the overall topsoil temperature in most areas of southern Minnesota remains too cold for good corn planting conditions. The long-term average soil temperatures on April 29 at Waseca are 52.2° F at the 4-in. level, and 53.2° F at the 2-in. level, which is very close to the minimally desirable daily average soil temperature for corn planting of 50° F at the 2-4-in. level. Normally, in early May, the soil temperatures warm up quite rapidly, so concern over cool soil temperatures becomes less of an issue. It is expected that most farm operators in southern Minnesota and northern Iowa will begin full-scale corn planting as soon as the field conditions are fit for planting.
Most university and private agronomists are encouraging producers to be patient with the initiation of corn planting in 2013, and to wait until soil conditions are conducive for good corn planting and seed germination. Planting corn into poor soil conditions increases the likelihood of poor stands and reduced yield potential. Given the high cost per acre of seed corn, and the limited availability of some of the best yielding corn hybrids in 2013, most growers do not want to take the risk of planting corn into poor soil conditions.
According to University of Minnesota and private seed company research, the “ideal time window” to plant corn in southern Minnesota in order to achieve optimum yields is April 20 to May 5. Even though spring planting is off to very slow start, compared to recent years, the good news is that there is still opportunity for timely corn planting. Based on long-term research, the reduction in optimum corn yield potential with planting dates from May 5-15 in southern Minnesota is usually very minimal. Even corn planted from May 15 to 25 has a good chance of producing 90-95% of optimum yield potential, assuming that we get some favorable growing conditions in 2013. Unless conditions turn very wet in the next couple of weeks, there is still a good chance to get a significant amount of corn in southern Minnesota and northern Iowa planted on a fairly timely basis in 2013.
The month of April has resulted in above-normal precipitation at most locations in southern Minnesota and northern Iowa. This has helped replenish some of the depleted stored soil moisture in the top five feet of the soil profile, most of which were at very low levels at the end of the 2012 growing season. At the U of M Research Center at Waseca, the total precipitation in April, through April 24, was 5.95 in., which is 2.40 in. above normal. Cumulative precipitation at Waseca in 2013, through April 24, was 11.53 in., which is 4.31 in. above normal. This added precipitation across the region has helped alleviate some of the short-term drought concerns, as we head into the 2013 growing season; however stored soil moisture remains a concern in portions of the western half of Minnesota.
Editor’s note: Kent Thiesse is a former University of Minnesota Extension educator and now is Vice President of MinnStar Bank, Lake Crystal, MN. You can contact him at 507-726-2137 or via e-mail at firstname.lastname@example.org.