By Dan Kaiser and Fabian Fernandez
A recent update has been made to University of Minnesota Extension’s suggested nitrogen (N) fertilizer rates for non-irrigated corn. The update adds data from the 2022, 2023, and 2024 growing seasons to our long-term dataset. The tables below summarize the current values which are included in the updated Fertilizing Corn in Minnesota web page and publication, as well as the Corn Nitrogen Rate Calculator.
The inclusion of the newer data resulted in an increase in suggested N application rates for both corn following corn and corn following soybean, with an increase in suggested N rates of around ten pounds per acre in both situations.
Regional Differences
This update reflects only non-irrigated corn grown in Minnesota for the bulk of the acres south of I-94. For those growing corn in the Red River Valley, we would still suggest following North Dakota State University guidelines for similar soils to what you have in your fields.
We have been looking at data from our irrigated corn locations for the past few years but have not seen a substantial, if any, increase in the amount of N needed for corn grown on irrigated sandy soils.
Source : umn.edu