ptown at Happys Bar and Grill, asking someone how deep they are planting their corn is a common way to open a conversation this time of year. Everyone has an opinion on the matter and everyone has their own experiences to back up their opinions:
If you dont see a few kernels on top of the ground, you aint planting shallow enough!
If you plant deeper than one inch, crust will get you every time!
If you plant too shallow, the crown roots will form at the surface and dry out!
The deeper you plant the seed, the deeper the roots will grow!
The reality is that the correct seeding depth should be based on the conditions of the seedbed and the 10-day weather outlook at the time of planting. The conditions of every one of your fields may vary dramatically enough as to warrant a slightly different seeding depth for each one. Conversely, you may end up using a common seeding depth setting for every field this year. The point is that you need to spend some time evaluating each field at the time of planting. Dont simply use the setting that you finished up with last year!
An all-purpose seeding depth for corn that is practical under many conditions is 1-1/2 inches. Planting shallower than that increases the risks associated with a rapidly drying seedbed, shallow crown root development and (in some locations) feeding damage by birds and rodents.
Under dry or potentially dry seedbed conditions, do not hesitate to increase seeding depth to 2 3 inches if that depth is where uniform moisture exists. Physiologically, corn can easily emerge from those seeding depths due to the ability of the mesocotyl to elongate in response to planting depth. If dry conditions exist at shallower depths and the short-term (10-day) weather forecast is dry, the risk associated with deeper planting is less than the risk of inadequate or uneven moisture at shallower depths.