By Steve Sexton & Brian Cornelious, PhD, Agricen
One of the pillars of the 4R approach to plant nutrition is applying fertilizer in the “Right Place.” This concept has opened the door for researchers and producers alike to examine practices that place small quantities of nutrients in a concentrated zone close to the point of seed placement. The use of starter fertilizer, which is aimed at getting plant nutrients in the “right place,” is becoming a common practice in some parts of the country. Here we look at starter fertilizer programs for corn from a nutrient efficiency perspective.
A standard starter program in the U.S. Corn Belt is 5 gallons of ammonium polyphosphate (APP; 10-34-0) plus 1 quart of zinc. 10-34-0 is a common polyphosphate fertilizer that must be converted into a plant-available form, called orthophosphate, prior to plant uptake and utilization. In fact, most starter fertilizers are primarily composed of the polyphosphate form of phosphorus.