It’s official now: some major Corn Belt states’ corn and soybean planting weather windows have officially shrunk. Purdue’s Ag Econ Prof Ben Gramig compared two time frames (1980-1994 versus 1995-2010). He found that Illinois and Iowa have on average 11-12% fewer hours per week to plant. That’s a half-day less per week than you used to have. In Indiana, that’s actually 1.1 fewer days per week, or a 24% decline.

So, Illinois farmers had 4.1 days of weather suitable for planting per week on average between 1995 and 2010—down from 4.6 suitable days per week between 1980 and 1994, the data show.

planting time

Indiana farmers had just 3.7 days per week suited to planting between 1995 and 2010, compared to 4.9 days in 1980 and 1994—a 24% drop!

Iowa farmers had 4 days per week suited to planting between 1995 and 2010, compared to 4.5 days between 1980 and 1994, an 11% drop.

More precipitation in the early growing season, and in more concentrated amounts, is well documented by climate-change scientists.

Good information to weigh when planning equipment and manpower needs, or choosing fertilizer application timing. No wonder large planters are popular.