Here’s How the Corn Crop Shaped Up in May Across Iowa, Illinois, and Nebraska

The month of May was a mixed bag for corn crop progress across Iowa, Illinois, and Nebraska, and, at times, within the same state. While some growers were stuck waiting for the rain to stop, others looked forward to its relief. 

By the end of the month, most farmers had wrapped up planting or were getting close.

Agronomists across the region shared what they were seeing in the fields — from rotary hoes breaking crust in Iowa to irrigation running in Nebraska. Here’s a week-by-week look at how planting and emergence shaped up in the heart of the Corn Belt.

Iowa

Corn planting by Iowa farmers in the month of May was behind average at first, but then it surged ahead of the five-year trend line as the month continued. As of the latest Crop Progress report, for the week ending June 1, planting progress had slowed to average.

Emergence was ahead of the five-year average all of May, as much as 9 points ahead the week ending May 18. By the week ending June 1, that gap decreased to one point

Here’s what Iowa agronomists and a farmer had to say as the month progressed.

Week Ending May 11 

Eric Wilson, an agronomist who supports southern and northeast Iowa, said on May 12 that southern Iowa was “essentially done” with corn planting, besides the last 5%, which he said “may drag on for a while,” at the time. 

Wilson said northeast Iowa made “tremendous progress” the week ending May 11. “Corn planting is more than 75% for most areas, and with the forecast I anticipate planting will be more than 95% completed within the next seven days,” he said. 

Cooler spring conditions slowed down emergence, Wilson said, and some parts of his coverage area received heavy rainfall that led to crusting issues. “I have seen more rotary hoes running on fields this year than I have in a long time, and so far that has helped tremendously in the areas where growers were fighting soil crusting issues. Overall, there has been very little replant of corn or beans at this point,” Wilson said. 

Overall progress was in good shape in the western portion of the state, too. “Last week and going into this week we have had a good window for corn and soybean planting,” Logan Dinkla said on May 12. He’s a Syngenta agronomist covering much of west Iowa. “Planting is either wrapping up or getting close to finished in the majority of my territory,” he said.

At the time, Dinkla said a lot of corn fields throughout the states were emerging, adding that for the fields he’d walked, emergence looked strong and even.

Week Ending May 18 

By May 18, southern Iowa had reached 95% corn planted, according to Wilson. Further, “Northeast Iowa had a big week this week,” he said, adding that the area had reached 80% corn planted or greater.

Wilson said of emergence at the time: “In northeast Iowa, emergence has been a challenge with early planted corn, but most areas have moved past this stage and things coming up later look very good.”

Throughout Dinkla’s territory, a lot of farmers had wrapped up with corn planting, he said on May 19. “I have heard a few reports of replanting, but it is not on a large scale.”

Dinkla said emergence in general looked good at the time, and he looked forward to upcoming rain “to help with emergence and herbicide activation” after a dry, windy week.

Kelly Garrett, a farmer in west-central Iowa, said corn planting in his area was finished. “With the warm temperatures we’ve experienced this year, the emergence has been very nice,” he said.

Week Ending May 25 

“Corn planting is essentially completed in my areas,” Wilson said on May 25. He said crops that had emerged looked good, and he anticipated corn that would emerge soon to have no issues. 

It was slightly cool and wet in southern and northeast Iowa the week ending May 25. “Much of my area received quite a bit of rain, and growers have been waiting for fields to dry out to resume field activities. Drying has been slow with the cooler conditions but temperatures are increasing as we get through Memorial Day,” he said at the time.

Week Ending June 1

“May ended dry with cooler than normal temperatures” in Dinkla’s territory, he said on June 2. He added that temperatures in the 60s slowed crop growth.

Despite slowed growth, the month ended on a high note for Iowa. “The majority of corn fields look really good,” Dinkla said. 

Illinois

Corn planting in Illinois was behind average most of May, as it was all of April. But progress ultimately caught up to the five-year average as of the latest Crop Progress report, for the week ending June 1.

May emergence started off behind average, jumped to ahead of average, and then returned to just shy of average as of the latest Crop Progress report.

Input from Illinois agronomists in different parts of the state help explain what was going on behind the numbers. 

Week Ending May 11

Just over a week into May, agronomist Phil Krieg described nonexistent corn planting in his coverage area, which includes part of southern Illinois: “Last week was another idle week in southern Illinois … We are sitting at the same planting progress of 3 weeks ago,” he said on May 12. 

“Emergence on the small percentage that is [planted] is very slow and the color is very pale,” Krieg said at the time.

The problem was the sheer amount of rain — the same issue southern Illinois growers faced most of April. “Temperatures warmed up nicely this past week, but after a couple warm sunny days, more rain fell,” Krieg said, adding that total precipitation ranged from 0.8 to 4 inches. 

Growers further north in the state were seeing conditions at the other end of the spectrum. 

Ryan Gentle, an agronomist covering much of western Illinois, said on May 12 that western Illinois was “virtually done” with corn planting. “Stands for the most part look good,” he said 

“Once you get about an hour south of Springfield, it is a different story though. Areas just east of [St Louis] have done very little planting of either crop due to rains almost everyday,” Gentle said.

Gentle said there was “virtually no rain” the week ending May 11 in western Illinois. “It really warmed up over the weekend, and crops have really taken off that were planted in April,” he said.

Week Ending May 18

“We finally saw an uptick in planting progress in some areas of southern Illinois,” Krieg said on May 19. At the time, he said corn planting was approaching 60% north of Route 16 across Illinois and 35% in the southern tip of the state. “The area between those two geographies in the heart of southern Illinois is stuck at less than 10% planted on corn,” he said.

“Overall emergence has been good, but there is a lot that remains to be seen based on the fact that so much is freshly planted in the last seven days,” Krieg said.

Week Ending May 25 

By the week ending May 25, Krieg said corn planting in southern Illinois was anywhere from 35% to 90% complete. “Most of this has been planted in the last seven days, so there is very little that has emerged,” he said on May 27. “For the small amount (10%) that is up, stands look good.” 

He described a surprising change for his coverage area at this time. “For the week of May 19-25, our biggest surprise was that we did not receive the predicted rain over Memorial Day weekend, so equipment rolled hard. This weekend was our greatest planting progress of the season so far,” he said.

In western Illinois, Gentle said corn planting was complete by May 27, and that post-spraying and sidedressing were the main activities. “Corn looks great, for the most part,” he said. “Early corn has almost closed the rows.”

Week Ending June 1

Krieg said “considerable progress” was made during the last week of May in his territory. “We are three-fourths complete with corn planting,” he said on June 1.  “The northern and southern parts of southern Illinois are complete, with the center between 50% and 60%,” he said. 

“Emergence looks good, but most of the corn is just emerging or will be emerging this week.  Some corn is approaching V5 in those areas in the north and south,” Krieg said.

In Gentle’s coverage area, most early-planted corn had been sidedressed and post-sprayed by the last week of May. He also said most was close to closing the rows, adding, “It looks very good right now.” 

Nebraska

Efforts by farmers in the Cornhusker State during the month of May pushed corn planting progress increasingly ahead of normal during the first couple weeks of the month, but in recent weeks progress has tracked largely with the five-year average.

Emergence has been ahead of average all month, but the gap has slowly decreased as the month has progressed.

Here’s how a Nebraska agronomist described progress throughout the month.

Week Ending May 11

A little more than a week into May, corn planting activity was already “winding down in Nebraska,” according to agronomist Travis Gustafson, who covers much of the state.

“There are still a few planters rolling, but for the most part growers are wrapping up their planting operations and transitioning into irrigating,” he said on May 12.

The irrigation was critical at the time. Gustafson described hot and dry weather for the week ending May 11, with “few prospects to get rain in the near term.” 

“Many parts of the state are under wildfire risk due to low humidity, wind, and stubbornly dry weather,” he said. “Farmers are relying on irrigation to maintain crop health.”

He said of emerging corn at the time, “Most corn in Nebraska that was planted in April is at the V1 growth stage, and fields are taking on a green hue.”

Week Ending May 18

By the week ending May 18, Gustafson said corn planting was “all but wrapped up in Nebraska.”  

“After a few weeks of heavy planting activity and no weather delays, we are basically done with planting. Many growers were trying to get done with planting so they could transition efforts into irrigating the crop up,” Gustafson said on May 19.

He said corn emergence had been excellent, adding, “Most growers planted deep enough to chase after what moisture was available. There was adequate moisture for germination and emergence but not much beyond that.”  

“Irrigation has been absolutely necessary to get the crop off to a good start,” Gustafson said, adding that “weather has continued to be hot and dry … with many comparisons to 2012.”

Widespread storms moved through the state at the end of the week, Gustafson said, bringing with them at least 1 inch of rain for many parts of the state. “This will shut off irrigation for a short period of time, but it will not bust the drought we are in,” he said at the time.

Week Ending May 25

On May 23, Gustafson said that Nebraska’s corn planting was “basically done.”

“Most corn is in the 2-3 leaf growth stage,” he said, adding, “Crop conditions are excellent with recent rains. There are small pockets of flooding in south central parts of Nebraska, but overall topsoil moisture is finally back to normal across the majority of the state.” 

“Nebraska has completely flipped weather wise from two weeks ago,” Gustafson said of the weather during the week ending May 25. “We have switched from overly dry conditions to finally getting adequate rains for the crop.” 

That rain — around an inch or more for most of the state — was quite a relief to the crop. “Corn was starting to show signs of stress prior to the May 18 rain events,” Gustafson said. 

Week Ending June 1

“Planters have been parked for a while, and the crop is off to a great start,” Gustafson said as of the last week of May in Nebraska. 

Gustafson said Nebraska’s weather at the end of May was relatively cool for the time of year. “[Growing Degree Units] accumulation is behind normal, so this has created lethargic growing conditions and tender crops,” he said.

He said the cooler temperatures had caused the corn to be shorter than it should be for its growth stage. 

The very end of the week saw a return to seasonal temperatures, Gustafson said, which he expected crops to respond to quickly. He also said soil moisture was adequate with “all the rains received over the last half of May.”