Adjust Planting Depth as Needed or Error on the Deep Side

"Planting depth in corn is very important," said John Swanson, Federated Agronomist at the Ogilvie location. It's a given to adjust planters first thing in the spring, but "we really should be making adjustments [on the planters] as we change soil types or as planting conditions change," said Swanson, adding that "shallow placement of seed increases the risk of poor nodal root establishment."

He further explained: "The mesocotyl is the portion of the corn shoot below ground between the seed and the crown of the plant. The crown is the base of the corn plant from which the permanent roots grow. We need to be sure we plant deep enough or the roots develop too close to the surface and we can end up with what is known as rootless corn . . . the condition where the permanent or secondary roots do not grow from the crown."

The end result is a serious stand-ability issue because the necessary roots for proper support are missing. "This is why we say, said Swanson, "in corn it is better to error deep on your planting rather than shallow."

Swanson indicated that a planting depth of 2 in. is optimal for corn in most situations in east central Minnesota and western Wisconsin, but as shallow as 1.75 in. is acceptable on tight clay soils, or as deep as 2.25 in. on sandy soils.

Check planting depth regularly and make planter adjustments as conditions vary. Talk to your Federated Agronomist with any planting questions.