By Daniel Kaiser, PhD, University of Minnesota
In areas where spring is cool and wet, banding fertilizer with the planter can benefit corn crops. Although application of dry fertilizer with the corn planter has played an important role historically, it has become less common with increasing acreages and planter sizes. Instead, liquid fertilizers have steadily replaced dry for supplying nutrients to the corn plant early in the growing season.
The primary benefit of applying low rates of fertilizer directly on the corn seed is more rapid growth early in the growing season. Increased early growth can be viewed as an insurance policy, ensuring that plants reach critical periods of growth faster. Low rates of phosphorus can significantly increase the amount of growth, even in fields where soil phosphorous test levels are high. Our research in Minnesota has demonstrated that as little at 10 lbs P2O5 applied with the planter can produce sizeable increases in plant mass early in the growing season. This increase has been shown to speed development and decrease the time to silking by one to two days.