Farmers often hear the mantra that all the companies have good corn hybrids. All hybrids are just about the same. That is not the case.

Speaking at a grain production meeting at the Wilson County Ag Center in Wilson, Ron Heiniger, North Carolina State University Extension corn specialist, emphasized the importance of maturity class when selecting corn hybrids to plant in the state. He said genetic selection is critical to success in maximizing yields.

A hybrid that tolerates stress and emerges well is key to better yields. Heiniger encouraged North Carolina farmers to plant at least 10 corn hybrids and to test those hybrids in their environment to see how adaptable they are to individual conditions.

“You use the maturity class that matches the resource you have. If you’re irrigating out of a pond and you know it’s going to go dry sometime during the season, you want an early hybrid because you want it to silk while water is still available,” Heiniger said.

Temperature

However, on sandier soils without irrigation, Heiniger said a late maturity hybrid works better because hot, dry weather in May can severely impact yields. Later hybrids will hold on for that next rain better than early hybrids. Managing your corn crop to match weather conditions is vital.

When leaf temperatures climb above 95 degrees Fahrenheit, the corn plant becomes stressed and uses more energy to keep cool. Pollination and grain fill must occur when temperatures don’t exceed 95 degrees.

As for nighttime temperatures, Heiniger noted that 74 degrees Fahrenheit is the highest temperature for optimum growth and  maximum grain fill.

“Corn doesn’t sleep at night. It’s working. Its gathering all of that energy during the day; it’s storing it in enzymes and other compounds and at night it is converting that energy into sugars and starches and packing it into the kernel. If that temperature is above 74, its burning some of that energy to try to keep cool,” Heiniger explained.

Weather forecasts point to a neutral climate pattern this year instead of the El Niño pattern seen last year. A neutral weather pattern means a cooler summer and a mild fall. In a neutral weather pattern year, Heiniger advised a later planting date, between May 15 to May 31.

Soil

One other method to manage high temperatures is to lower the plant population to better manage water and capture more light. Heiniger said a rate as low as 24,000 seeds per acre could be used on very sandy soils without sacrificing much yield potential.

In addition, 20-inch rows offer a cooler canopy than 36-inch rows because spacing the plants out wider within the row gives them a little bit more water and allows them to better tolerate higher temperatures.

Soil health is critical to good yields and Heiniger urged farmers to take steps that increase porosity. “Fifty percent of that soil should be air and water. Keep that water in balance. I don’t want saturation. I want my soils to drain well. I want good carbon and organic matter. Do what you can to build soils,” Heiniger said.

Heiniger does like cover crops and other soil building practices, but he acknowledged that building soil health is a long-term job. So, what can a farmer do in 2020 to make a difference in yield?

“Here’s what I’m going to suggest to you in 2020. Make your soil around the seed better. I’m going to manage right there by the seed. I’m going to make sure it has good drainage. I’m going to make sure if that pH is wrong, its wrong someplace other than around that seed. I’m going to make sure the soil biology in that area is the best I can make it. I’m going to make sure my phosphorous concentration is good in that area. I’m going to make sure I have nitrogen available in that area,” Heiniger said.