Table 27. Typical Application Rates Of Micronutrient Fertilizers1

Typical FertilizersApplication Rates
Boron: Borax (10.6% B)Soil application0.5 - 1 lb boron/acre for most crops; up to 2.5 lb/acre for heavy feeders, e.g., alfalfa, beets, turnips
Foliar spray - perennials0.2 lbs boron/100 gal water one to three weeks after petal fall
Foliar spray - annualsspray regularly, e.g., 0.1 lb boron/100 gal water weekly for eight weeks
Copper: Copper sulfate (25-35% Cu), copper oxide (75% Cu)Soil application2 - 6 lbs copper/acre; double or more for muck soils
Foliar spray0.8 lbs copper/100 gal water
Iron: ferrous sulfate (19% Fe), NaFe-EDDHA (6% Fe), NaFe-EDTA (5-14% Fe)Foliar spray3% solution of ferrous sulfate, possibly including a wetting agent, at a rate of 120 - 180 gal/acre, started when deficiency symptoms begin and continued at 2-week intervals until they disappear
Manganese: manganous sulfate (26-28% Mn), Mn-EDTA (12% Mn)Soil application 5 - 10 lbs inorganic manganese/acre, banded; broadcast application is much less effective
Foliar spray0.5 - 1 lb manganese/100 gal water, either inorganic or chelated, repeated two or three times
Molybdenum: Ammonium or sodium molybdateSeed treatment0.25 - 0.5 lbs molybdenum/acre
Soil applicationlime usually helps; 0.02 - 0.4 lbs molybdenum/acre
Zinc: Zinc sulfate (23-35% Zn)Soil application2 - 20 lb zinc/acre
Foliar spray (rare)0.125 - 2.2 lbs zinc/100 gal water, sprayed regularly until the deficiency symptoms disappear

1 Data is from [50], [57], [51], [22].   [return to top]

© 2013 Robert Parnes

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