Of those three, calendar and temperature can be disregarded at a certain point, but soil moisture cannot.
In 2022, the calendar and thermometer went out the window. Across most of the region, the crop was planted between May 15th and June 15th.
For May-planted corn, forget the calendar and soil temperature. WHAT?!? Most people would not expect that comment. To clarify, if the forecast looks decent, it’s time to plant corn, but if – and only if – soil moisture is also favorable. With over 14 hours of sunshine and mid-May temperatures averaging 70 degrees, the soil temperatures will follow.
However, soil moisture is just as crucial in May as in April. Don’t mud the crop in, as that is always a recipe for disaster.
I’ve been in many fields where the grower was trying to finish planting the final few acres in the pouring rain. These are always the lowest-yielding parts of the field, regardless of whether the soil type is sand or gumbo.
Everyone gets anxious for the weather to cooperate while waiting to plant, but wet ground is never a time to be in a hurry. Stick with your original plan, staying with maturities until at least May 20. Even with more rain in the forecast, a 10% yield hit planting on May 20 is far better than a 50% hit by planting in saturated soil on May 9.