Richard Taylor, Extension Agronomist; rtaylor@udel.edu
With temperatures in Delaware bouncing from below freezing in the mornings to only the 40s or 50s in the afternoons, corn growers need to curb any impatience they feel about getting that early jump on corn planting until after the soil temperature in the upper few inches of soil warms above 50°F and prospects are for it to continue to rise. Corn germination and growth does not start until the soil temperature at seeding depth is 50°F or greater. Soil temperatures that fluctuate around 50°F or remain in the low 50s for extended periods lead to slow, variable corn emergence that can have strong negative consequences on yield potential.
If the number of acres that you’ll eventually plant to corn necessitates that you get a very early start, I suggest you plant first those fields that are likely to have the lowest yield potential. Save your highest yielding fields and hybrids to plant during the ideal planting window of April 20 to May 5. By planting your best fields during this window, you will ensure the best possible stand and yield. You also should increase your farm-wide average yields in this way.