Starter fertilizer is necessary for high corn yields at our Northern latitude, and especially with high residue farming systems. A common way to apply dry starter fertilizers has been the 2×2 method, two inches off the row and two inches below the seed. However, recent research has found that surface banding of liquid fertilizer, 2″ off the row, can be just as effective. Surface banding eliminates the need for an extra set of openers, allows greater residue levels and reduces required planter weight. It also allows greater fertilizer rates than popup methods (with the seed).
These results were found by researchers in both Kansas (2000-2002) and Minnesota (2004-2006) despite different soils and environments. In the Kansas study, the 30-30-5 starter fertilizer used in the dribble application was made using a combination of liquid 10-34-0, 28% UAN and potassium thiosulfate. The Minnesota research used a 20-20-10-10(S) fertilizer made by combining 10-34-0, UAN, potassium thiosulfate, and ammonium thiosulfate, in a high P-testing soil.
Sources
- Effects of method of application and composition of starter fertilizer on irrigated corn. Kansas State University.
- Optimum placement of NPKS starter fertilizers in high-testing soils. University of Minnesota.