By: Mike Toohill, AgVenture WSC

Bloomington, IL

I’m not sure who first came up with this quote but I think about it every time soils dry and warm way ahead of schedule in the spring. Most years the above words first come to mind around St. Patrick’s Day if top soils are dry and temperatures are on rise. But this year I started to get concerned about the temptation to plant too early by late February! Not only has it been very dry this month in most of the Midwest (see the 30-day moisture departure map below left) but February has been a record setting month as far as above mean temperatures (below right). In fact, I have never seen a monthly map that warm…

What are the main concerns about planting corn and soybeans in the heart of the belt in March? Of course, increased replant risk for both crops first comes to mind. Maybe not as obvious, the “gray” areas often associated with uneven and slow emergence when corn struggles to establish a stand in cold and wet soils. Soybeans are more tolerant to stand loss and lack of uniformity but some high yield growers have elaborated on the importance of keeping the cotyledons as long as possible and we often end lose at least one in the crust resulting in weak plants (if they survive). Not as common but common enough, what if we get a warm week in late March and the crops quickly emerge? This increases April and May frost risk to both crops, especially in high residue situations.

Will March weather “slow the roll”? Early March looks to continue the warm with increased rain chances but the monthly maps don’t offer much weather “direction”.

Risk compared to reward? Even with all the talk about earlier planting soybeans, April 10th is the “magic” planting day for Illinois according to the data I have seen during winter meetings. More and more corn growers are valuing “picket fence” stands and that is not likely with March planting dates. Thus, I revert back to my first sentence: “Not much good happens when corn and soybeans are planted in March in the Midwest”.