Focus on ag: Farmers waiting for favorable planting weather

Kent Thiess
Farm Management Analysist
Kent Thiesse

Like the start of a big race or the beginning of a championship game, many farmers across the Midwest are waiting for favorable weather to begin full-scale fieldwork.

Very cold temperatures and frequent rainfall or wet snowfall events across the region have resulted in almost no major fieldwork being initiated as of April 11 in most areas. It appears that the 2022 planting season may be somewhat later than last year in much of the Upper Midwest, Farmers are hopeful that fairly favorable corn planting conditions develop in the last half of April, which would still provide a nice window for optimal corn yields in 2022.

Once planting season is initiated, farmers in most areas should be well within the U.S. Department of Agriculture Risk Management Agency guidelines to maintain full crop insurance coverage for the 2022 corn and soybean crop.

The earliest corn-planting date allowed by the Risk Management Agency to maintain full crop insurance protection in most of Minnesota and Iowa is April 11, while April 21 is the earliest planting date allowed for soybean planting for full insurance coverage. For initial and final planting dates in all states and other federal crop insurance information, visit https://www.rma.usda.gov/.

Many areas of the Upper Midwest and plains states have received some much-needed rainfall in late March and early April; however, there are still large portions of the region that remain quite dry heading into the spring planting season.

The most recent U.S. Drought Monitor on April 7 listed only 8% of Midwest states, which include Minnesota, Iowa, Illinois, Indiana and Wisconsin, as having “moderate” drought conditions, with 26% of the area reporting abnormally dry conditions, primarily in eastern Minnesota, central Iowa, northern Illinois and southern Wisconsin. By comparison, a year ago in early April, nearly half of the area in the Midwest States was listed in some level of drought conditions.

The situation is much different in the plains states, which include Nebraska, South Dakota and North Dakota, with nearly 87% of the region listed at some level of drought in early April. Nearly 45% of the area is listed in the severe or extreme drought categories. Only eastern North Dakota and South Dakota and eastern Kansas were not categorized as having drought conditions. Many portions of the plains states have remained in drought conditions for two years or longer.

Soil temperatures in early April have remained quite cold and below levels for ideal corn planting in many areas of the Upper Midwest. At the University of Minnesota Research and Outreach Center near Waseca in southern Minnesota, the average 24-hour average soil temperature on April 9 and 10 was below 40 degrees at the 4-inch level. This range is well below the minimum desired soil temperature of 50 for good corn planting and seed germination conditions.

Farmers and agronomists tend to pay close attention to soil temperatures early in the growing season. However, soil temperatures become less of a concern by late April. At that point, getting the crop in the ground gets to be more of a priority rather than soil temperatures, as the ideal corn planting window gets much shorter.

Research shows that 50% corn emergence will occur in 20 days at an average soil temperature of 50 degrees, which is reduced to only 10 days with an average soil temperature of 60. The recent soil temperatures would provide some concern for having favorable conditions to achieve good corn germination and early seedling growth.

The very cool soil temperatures are also not very conducive for the initiation of soybean planting, as soybeans generally require even warmer soil temperatures than corn for good germination. Every year is different, and agronomists encourage producers to adjust to soil conditions and weather forecasts when making corn and soybean planting decisions.

Soil conditions prior to recent rains were described as fairly ideal for spring planting by farm operators and agronomists in many areas the Upper Midwest. If we can avoid any further significant amounts of precipitation in the next week or so and we get some warmer temperatures, most crop producers in the region should be able to begin full-scale corn planting once soil conditions are fit. Following the completion of corn planting, many farmers will be moving directly into planting their soybean crop, provided that field conditions remain favorable.

Beyond the variation in topsoil moisture conditions that exist across the Upper Midwest and plains states, there is also a wide variation across the region in the amount of stored soil moisture, as we head into the 2022 crop year. Stored soil moisture levels in many areas were depleted to very low levels during the height of drought conditions in June and July of last year. However, some of the region, especially in western and southern Minnesota, northern Iowa and the eastern Dakotas had some fairly significant recharge of stored soil moisture last fall and early this spring. In the areas that are listed in the more severe drought categories, available stored soil moisture will likely be a much bigger concern heading into the growing season.

Unless conditions turn very wet in the few weeks, a large majority of corn in much of the Upper Midwest could still be planted by late April or early May this year. Corn planting delays beyond the first week of May can significantly affect final corn yields.

In both 2018 and 2019, a majority of the corn in Minnesota was planted from mid-May to early June. Only 2% of the corn in Minnesota had been planted at the end of April in 2019, which was about 15 days behind normal. Minnesota’s corn yield declined from record yield levels in 2015, 2016 and 2017 to 182 bushels per acre in 2018 and only 174 bushels per acre in 2019.

Historically, early planting of corn usually leads to higher-than-normal State average corn yields in Minnesota and other Upper Midwest states. In six of the 10 years that 50% or more of the corn acres in Minnesota have been planted in April or the first few days of May, the state has set a record corn yield.

In 2015, corn planting in Minnesota was 83% completed by May 3, resulting in a record yield of 188 bushels per acre, which was followed with 89% of the corn planted by May 8 in 2016, again resulting in another record statewide corn yield of 193 bushels per acre. One exception was in 2017, when most of the Minnesota’s corn was planted in the first two weeks of May. Very favorable growing conditions throughout the year in most areas resulted in statewide record corn yield in 2017. In 2020, when 76% of the corn was planted by May 3, the statewide corn yield was 192 bushels per acre, just short of the statewide record corn yield of 194 bushels per acre in 2017.

The estimated the 2021 average corn yield in Minnesota was only 178 bushels per acre, which was well below other recent statewide average. Even though 71% of the statewide corn acreage was planted by May 3 in 2021, drought conditions in many portions of the state during the critical crop growing months of June and July greatly reduced corn yields in many portions of western and southern Minnesota. In areas of the state that received adequate rainfall at critical times for corn development, the corn yields in 2021 were above average to near record levels. Provided there are favorable growing conditions later in the growing season, the common denominator for the exceptional corn yield years in Minnesota has been that a large majority of the state’s corn crop was planted by the end of April or in very early May.

Once farmers have completed planting their corn acres, most move directly to soybean planting. The ideal planting window for achieving favorable yields is much wider for soybeans than corn.

The ideal soybean planting timeframe in most areas of the Midwest extends from late April until about May 20 or slightly beyond, so there will be plenty of time to get the 2022 soybean crop planted. However, research shows that with favorable growing conditions there  is a yield advantage by planting soybeans in late April or early May as opposed to later in May.

For additional information contact Kent Thiesse, farm management analyst and senior vice president, MinnStar Bank, Lake Crystal, Minn., at 507-381-7960 or kent.thiesse@minnstarbank.com.