When planting corn early in the season and in dry soils, these three practices will give the crop a fighting chance:
• Plant deeper. “The standard planting depth of 1.5 inches may be too shallow. When the seedbed is dry, or is likely to become dry, planting depth should be increased to 2 to 3 inches if that is where there is uniform soil moisture,” says Jonathan Kleinjan, South Dakota State University Extension crop production associate. However, don’t plant deeper than 3 inches. “Moisture conditions, and thus ideal planting depth, may vary throughout the season and even throughout each field. It is important to thoroughly check the conditions in each field prior to planting.”
• Factor in the weather. Base the ideal planting depth on soil conditions and the near-term or 10-day weather outlook. Corn seeds will absorb water in temperatures below 50 degrees F, but they will not begin root or shoot growth, potentially leading to seed rot and poor emergence. “Corn hybrids with increased cold tolerance and fungicide seed treatments can help plant survival when planting at temperatures below 50 degrees F,” Kleinjan says.
• Calculate the frost risk. Early planting potentially can lead to early germination and plant growth. The growing point of a corn plant emerges at the V6 growth stage after about 475 growing degree days. “Most research suggests that corn damaged by frost prior to the V6 growth stage will retain nearly 100% of yield potential,” Kleinjan says. Corn plants at the V9-V12 stage damaged by a late-season frost should recover, but can have delayed maturity, reduced plant height and yield reductions of up to 50%. You can use an online tool to predict corn growth stages, accumulated GDDs and spring or fall frost risks for any county in the U.S. Corn Belt. See mygeohub.org/groups/u2u/gdd.
Source: SDSU Extension
This article published in the April, 2016 edition of DAKOTA FARMER.
All rights reserved. Copyright Farm Progress Cos. 2016.