Like the start of a big race, or the beginning of a championship game, farmers in Minnesota and Iowa are anxiously awaiting the initiation of full-scale field work. Very cool temperatures and moist soil conditions have existed across the region during the first three weeks of April, resulting in excess soil moisture and cold soil temperatures, which has not been conducive to the initiation of corn planting  in Minnesota and Iowa. A few farm operators have planted some early peas and small-grain crops in isolated locations. 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, MN, the average soil temperature at the 4-in. level on April 21 was only 40° F and 41° at the 2-in. level – far too cold for good corn-planting conditions. The long-term average soil temperatures on April 21 at Waseca are 48.9° F at the 4-in. level and 49.3° 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 late April and early May the soil temperatures warm up quite rapidly, so there appears to be no reason to delay corn planting in 2011 due to soil temperatures, once the field conditions are fit for planting. The stored soil moisture in the top 5 ft. of the soil profile is at or near capacity in most areas of southern and western Minnesota as we head into the 2011 growing season.
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 a much slower start than in recent years, the good news is that we are still in the early portion of this ideal time window for corn planting. Unless conditions turn very wet in the next couple of weeks, there is sill a good chance to get a significant amount of corn in southern Minnesota and northern Iowa planted during the ideal window in 2011.
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 [email protected]