This University of Minnesota Extension guide, "Fertilizing Corn in Minnesota" (revised 2025), devotes its "Micronutrient needs" section to corn. Overall, corn takes up less than one pound of micronutrients per acre, and while micronutrients are needed for optimal growth, they may not need fertilizer application.

Zinc (Zn) is identified as the only micronutrient likely needed in a Minnesota corn fertility program, and corn is the only agronomic crop that consistently responds to Zn fertilization. The DTPA soil Zn test reliably predicts need. Recommended rates by DTPA soil Zn test level: 0.0-0.25 and 0.26-0.50 ppm = 2 lb/acre banded or 10 lb/acre broadcast; 0.51-0.75 ppm = 1 lb/acre banded or 5 lb/acre broadcast; ≥0.76 ppm = 0 lb/acre (no response expected). Banded Zn is generally preferred for immediate response, though broadcast provides better carryover to future years. Most Zn sources are equally effective except large zinc oxide particles; chelated Zn (especially EDTA-chelated) offers the most stable availability across soil pH and is often used in liquid starter fertilizers, though it costs more per lb of Zn and does not improve response on soils already testing ≥0.75 ppm.

Boron (B) is unlikely to increase corn yield across Minnesota soils; only a small chance of response exists on sandy soils with <1.0% organic matter and B soil test ≤0.08 ppm. If deficiency is suspected, trial applications should not exceed 1-2 lb B/acre broadcast, and there are no guidelines for foliar B due to toxicity risk at low rates.

Iron (Fe), copper (Cu), and manganese (Mn) fertilization is not recommended for Minnesota corn under current guidelines, as these micronutrients are not considered yield-limiting in the state's corn production systems.