Growers worried about delayed planting for corn, take heart – late-planted corn sometimes has reaped better yields than early planted corn, says an agronomist in the College of Food, Agricultural, and Environmental Sciences at The Ohio State University.

It’s true that the optimal time to get corn planted in southern Ohio is between April 10 and May 10 and in northern Ohio between April 15 and May 10, based on historical crop data, said Peter Thomison, an Ohio State University Extension agronomist. OSU Extension is the statewide outreach arm of the college.

But this season’s cooler temperatures and wet field conditions have delayed many growers across the region from getting their corn crops completely planted, Thomison said.

Across Ohio, as of the week ended May 15, only 34 percent of corn was planted, according to the U.S. Department of Agriculture’s National Agricultural Statistics Service. That compares to 71 percent that had been planted by the same time last year and 54 percent that had been planted on average during the same time period over the past five years, the agency said.

“Corn and soybean planting progress is behind both last year and the five-year average, as farmers have been unable to get into fields that are soggy and, in some cases, in standing water,” Cheryl Turner, Ohio State statistician with the agency, said in a written statement.

But for growers who haven’t gotten all their corn crops planted yet, all is not lost, Thomison said.

Based on historical data since 1980, lower grain yields are not a certainty with late-planted corn, he said.

“Since 1980, there have been significant planting delays associated with wet spring weather in nine years,” Thomison said. “And while, in five of those years, yields were lower than the state average, in four of those years, yields were similar or higher than the statewide average yield of the previous five years.

“And in one of those years, 2009, when only 42 percent of the crop was planted by May 20, growers saw the third-highest corn yield on record – 171 bushels per acre.”

That’s because factors other than planting date are important considerations when it comes to corn yields. Weather conditions and rainfall in July and August also play an important role in yield determinations, he said.

For example, wet weather conditions caused planting delays for many growers in 2011, with most growers not getting any of their corn planted by May 30, Thomison said. However, because growing conditions were generally highly favorable for corn after planting, many growers were still able to produce crops with good yields that year, and, in some cases, yielded 6 bushels above the trend line, he said.

“Growers who are still getting their crops in now still have the potential for good yields,” Thomison said. “Even growers who don’t get all their crops in until the early days of June could still get a decent crop out.

“Weather conditions such as good rainfall and warm temperatures in July and August are probably the most important factors that determine yield. But if late-planted crops experience severe moisture stress during pollination and grainfill, then crop yields may be significantly lower than average.”

Source: Ohio State University Extension