Delayed Corn Planting and Hybrid Maturity Switching

R.L. (Bob) Nielsen , Agronomy Department , Purdue University, West Lafayette, IN 47907-1150

Originally published in Purdue Pest Management & Crop Production Newsletter (5/5/95)

The guys down at the B&B Pitstop Cafe have been singing the blues lately about the delays in the start of serious corn planting around the state. Some of them are even wanting to begin switching their full-season corn hybrids for earlier maturing ones because they are worried about the shortened growing season. Is this fearmongering warranted? The answer is a resounding NO!

Based on research conducted the past four years by myself and Peter Thomison at The Ohio State University, there is little reason to switch from normally adapted hybrid maturities to earlier ones until at least the early part of June. Corn hybrids appear to somehow adjust to delayed planting by flowering and maturing in fewer heat units than corn planted 'on time'.

IF the rainy weather continues through the middle of May, growers should AT THAT TIME, begin talking with their seed dealers about the availability of earlier maturity hybrids. If large areas of the state are faced with delayed planting by that time, seed companies will need some lead time to line up supplies of desired hybrids.

BUT, for heaven's sake, don't actually begin switching to earlier hybrid maturities until planting delays approach the early part of June.