Figure 3 shows that yield was similar for planting depths from 1.0 to 3.0 inches, but dropped off at 3.5 inches in the April 11 planting, likely related to the lower stands associated with that planting depth. Yields were highly variable in the May 3 planting due to conditions unrelated to planting depth (heat during silking, rooting depth), but did not change appreciably with planting depth. The 1.5 to 2.0 - inch planting depths resulted in some of the most consistent yields with both planting dates.
These results support current recommendations that corn be planted at 1.5 to 2.5 inches depending on soil conditions. Corn can be planted a bit deeper than 2.5 inches and shallower than 1.5 inches in certain conditions with a minimal impact on yield.