Iron (Fe)
Iron is a micronutrient that gives grass its deep green color. Unlike nitrogen, iron produces a rich, dark green without pushing excessive blade growth. It is especially valuable for centipede grass and St. Augustine, and for greening up a lawn mid-summer without risking disease.
Iron is essential for chlorophyll production — the pigment that makes grass green. A lawn deficient in iron appears yellow-green (chlorotic). Iron supplements give you the color boost of nitrogen without the growth flush that invites disease in hot weather.
Application: Available as liquid iron (ferrous sulfate or chelated iron) or granular. Liquid iron works faster. Apply to dry grass and water in lightly.
Caution: Iron stains concrete, driveways, and pavers permanently. Sweep granules off hard surfaces before watering.
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