When it comes to planting corn, how deep is deep enough and how shallow is too shallow? In a planting depth demonstration, DuPont Pioneer agronomy researchers evaluated how corn development is affected when planted at different depths. The results confirmed optimal planting depth in the Midwest is typically 1 ½ inches to 2 inches.
There are a number of reasons why growers may find varying planting depths within a single cornfield. These include planting at too high of speed, planting into heavy residue and planting in less than optimum soil conditions.
Corn planted too shallow may result in:
Decreased ability to uptake water and nutrients through the roots
Potential to develop "rootless corn syndrome" causing plants to fall over due to the lack of nodal root development in dry soil
Increased potential for herbicide injury due to exposure of corn seedlings to herbicide residues
To achieve optimum planting depth this spring, consider the following planting depth recommendations:
Set the planting depth in the field, with the planter being pulled at full operating speed
Check for good seed-soil contact
Slower planting speeds achieve more uniform planting depths
Utilize in-row residue management equipment when needed
Utilize in-furrow seed depth control devices
Additional management tips, including proper plant spacing to maximize yield, are available at www.pioneer.com.