Column: Wetter May pattern might not impede U.S. farmers' corn plans

FORT COLLINS, Colo. (Reuters) - U.S. farmers are ahead of schedule in planting the 2021 corn and soybean crops to kick off May, the busiest planting month. The weather forecast is not exactly wide open to facilitate seamless planting in the coming weeks, but attractive prices may override those imperfections.

FILE PHOTO: A truckload of corn is dumped into a chute at the Lincolnway Energy plant in the town of Nevada, Iowa, December 6, 2007. T REUTERS/Jason Reed/File Photo

The widespread dry soil conditions have been both a blessing and a curse since planting is more efficient, but pressure is higher to receive sufficient moisture down the road. A flip to a wetter pattern right now would help the newly sown crops, and it might not necessarily derail planting plans either, given strong profit potential.

As of Sunday, some 46% of the U.S. corn crop was planted, up from 17% a week earlier and above the five-year average of 36%. Analysts had pegged the progress at 44%.

So far, the 2021 corn planting campaign is tracking very similarly to that of 2015, when 50% of the crop was planted by the same date. Above-average progress was maintained throughout May 2015 despite a bit more rainfall than average in the Midwestern states.

That is good news for this year’s efforts because forecasts suggest a more active weather pattern through at least mid-month. The rains would be much-needed in many areas following a bone-dry April, though any heavier or persistent rains could keep planting progress in check.

The market still expects a notable rise in corn and/or soybean acres in the June acreage survey after the March intentions fell well short of predictions, though corn acres are not usually added during wet Mays.

But previous comparisons might be out the window as new-crop corn futures have gone on an unprecedented rally in the last couple of months, further complicating the possible acreage scenarios for both the June survey and final number.


In the last 40 years, final corn acres were higher than March planting intentions 15 times. May precipitation was materially above average in only two of those 15 cases: 2004 and 2017. The 2017 acreage gain was minimal, though 2004’s addition is a major outlier when considering the weather.

May 2004 was the wettest Midwestern May in 126 years of records, and final corn acres rose by nearly 2 million from intentions that year. But planting progress was also lightning-fast in 2004 thanks to a dry April, and corn planting reached 84% complete by May 9, still a record for the date.

That means the 2004 corn acreage was not riding on a dry May, but the deluge still did not stop farmers from expanding area over March intentions by one of the largest-ever degrees. Similar to this year, new-crop corn and soybean prices in spring 2004 were at multi-year highs, adding extra incentive.

Wet weather plus higher prices motivated farmers to plant corn in 2019, which featured the second-wettest Midwestern May and historic planting delays. Market participants thought corn acres would plunge from intentions, but farmers forged ahead and unexpectedly planted corn well into June.

Planting so late and into very wet soils raise yield risks for corn, and that was confirmed after 2019 with disappointing results. However, the 2004 crop notched by far a record yield with ideal summer weather and it remains among the most impressive harvests.


There is not a great correlation between soybean acreage gains or losses and May precipitation likely due to farmers’ ability to successfully plant beans in June if they need to. But at the rate they are going this year, there might not be any soybeans left to plant by the end of this month.

About three-fourths of U.S. soybean planting is typically completed by the end of May, excluding the super-delayed 2019 crop. As of Sunday, some 24% of the crop had been sown, a record pace for the date and well above the five-year average of 11%.

But are farmers actually ahead of their normal pace or is the “normal” pace no longer representative? U.S. growers typically plant corn before soybeans since later-planted corn introduces more yield threats, though many farmers are now opting to plant soybeans first as that has been credited for larger yields in recent years.

This phenomenon is likely on display in Illinois, the nation’s top soybean producer. As of Sunday, some 41% of the state’s soybeans were planted, up from 18% a week earlier and far above the five-year average of 14%. However, the state’s corn progress had reached 54%, just 5 percentage points above the average.

If this is truly a new normal, it adds nuance to historical references, which may not inform as well on potential outcomes. But it is interesting to note that final soybean acres in recent decades were less likely to be larger than in March whenever early to mid-May planting progress was well ahead of normal.

In the fastest soybean-planting years, the explanation seems to be that corn planting was also fast and corn acres were added rather than soybean acres. That theory breaks down for many other years, though, and more investigation is needed.

The opinions expressed here are those of the author, a market analyst for Reuters.

Editing by Matthew Lewis