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Max out your corn yield potential

The world's appetite for corn isn't getting any smaller, and that's got U.S. farmers under the gun to raise the best corn crop they can this year. Doing so starts from the ground-up and begins right now, as you're just getting your crop started.

"Mistakes made during crop establishment are usually irreversible, and can put a 'ceiling' on a crop's yield potential before the plants have even emerged," says Ohio State University Extension agronomist Peter Thomison.

So, what are some ways to get your crop off to the best possible start? It starts with the soil, Thomison says. Make sure you perform any tillage under the right conditions so you're not doing yourself more harm than good.

"Avoid working wet soil and reduce secondary tillage passes. Perform secondary tillage operations only when necessary to prepare an adequate seedbed. Shallow compaction created by excessive secondary tillage can reduce crop yields," he says. "Deep tillage should only be used when a compacted zone has been identified and soil is relatively dry. Late summer and fall are the best times for deep tillage."

This spring's been characterized by conditions early in the season that have allowed a lot of fieldwork and planting to get done early. But, don't be lulled into complacency by any early progress you are making. Keep on top of it so you don't wind up on the other end of the spectrum. Make sure you get your planting done not long after the optimal planting date for your area.

"If soil conditions are dry and soil temperatures are rising fast, and the 5- to 7-day forecast calls for favorable conditions, start planting before the optimum date," Thomison says. "During the 2 to 3 weeks of optimal corn planting time, there is, on average, about one out of three days when field work can occur. This narrow window of opportunity further emphasizes the need to begin planting as soon as field conditions will allow, even though the calendar date may be before the optimal date."

But, if you are planting ahead of the normal time, make sure you're working in your fields that are ready. If you've dealt with cool, damp conditions, don't "mud in" corn just for the sake of getting it in the ground early.

"Avoid early planting on poorly drained soils or those prone to ponding: Yield reductions resulting from "mudding the seed in" may be much greater than those resulting from a slight planting delay. Cold water can cause similar injury to seedling structures as they emerge during germination," Thomison says. "Such injury in corn seed ruptures cell membranes and results in aborted radicles, proliferation of seminal roots and delayed seedling growth."

Regardless of your soil conditions, make sure you're planting at the right depth. If you're wary of potential frost damage, it may be better to plant at a more shallow depth. If your soil's already warm and dry, think about a deeper seeding depth.

"Adjust seeding depth according to soil conditions: Plant between 1 1/2- to 2-inches deep to provide for frost protection and adequate root development. In early to mid-April, when the soil is usually moist and evaporation rate is low, seed should be planted no deeper than 1 1/2 inches," Thomison says. "When soils are warming up and drying fast in late May or early June, corn may be seeded more deeply, up to 2 to 2 1/2 inches on non-crusting soils. Consider seed-press wheels or seed firmers to ensure good seed-soil contact."

Finally, don't take a one-size-fits-all approach to seeding rates. If you're in one of your best fields, don't be afraid to bump up the seeding rate. Also consider the soil's ability to hold water.

"Adjust planting rates by using the yield potential of a site as a major criterion for determining the appropriate plant population," Thomison says. "Follow seed company recommendations to adjust plant population for specific hybrids."

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