Iron (Fe)
The most commonly applied micronutrient in lawn care. Iron is essential for chlorophyll production — the pigment that makes grass green. Iron applications produce deep, rich green color without stimulating excessive growth. See also: Iron (Fertilizer section).
Iron is absorbed by grass roots and used to produce chlorophyll. When iron is deficient, new growth appears yellow-green (a condition called iron chlorosis). Highly alkaline soils can lock up iron and make it unavailable to plants even when iron is present in the soil.
Application: Liquid chelated iron or ferrous sulfate solution gives the fastest color response (visible in 3–5 days). Granular iron works more slowly.
Chelated vs non-chelated: Chelated iron stays available in a wider pH range and is more resistant to being tied up in alkaline soils. Worth the extra cost if your soil pH is above 7.0.
More on Micronutrients
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