Effect Of Delayed Planting On Corn Yield

With another storm system rolling through Kansas this week, more questions have been coming in about the effect of delayed planting on corn yield. A series of studies at K-State looking at delayed corn planting was conducted a few years ago.

Three hybrid maturities were tested: 100-, 108-, and 112-day. Over the two years and three locations (Belleville, Manhattan, and Hutchinson), there were three distinct environments (as related to the environmental stress):

• Low Stress – where rainfall was favorable during the entire growing season
• Early Stress – where cool temperatures and wet conditions limited early corn growth
• High Stress -- where conditions (rainfall and temperatures) were favorable early in the season, but the mid-summer was hot and dry

In the Low Stress environments, yields were reduced by less than 20% when planting was as late as mid-June. Yields were not statistically different for any planting date before May 20 (starting from early April). Maximum yield in these non-irrigated environments was 176 bu/acre. The yield responses were similar for hybrids of all maturities.

In the Early Stress environments, yields actually increased as planting was delayed until late June. This response was similar for all hybrid maturities. These environments had favorable temperatures and rainfall throughout July and early August. Maximum yield in these environments was 145 bu/acre.

In the High Stress environments, yields dropped by about 1% per day of planting delay, depending on hybrid maturity. The shorter-season hybrids had the best yields if they were planted before late May (maximum yield = 150 bu/acre), but all hybrids had yield reductions of more than 50% when planting was delayed until early to mid-June.

Source : ksu.edu