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Lawn Health Guide

Yellow Grass That Won’t Green Up? It’s Iron Chlorosis.

Understanding DFW’s alkaline clay, why your lawn is struggling to absorb nutrients, and how professional diagnosis can fix it permanently.

Symptom Diagnosis: Is It Really Iron Chlorosis?

Learn how to distinguish iron chlorosis from other common turf issues in North Texas.

Interveinal Chlorosis Explained

The hallmark sign of iron chlorosis is “interveinal chlorosis.” This means the tissue between the leaf veins turns yellow or pale green, while the veins themselves remain a darker green. In severe cases, the entire leaf may turn white and begin to die at the edges.

Not Nitrogen Deficiency

Unlike nitrogen deficiency where the entire leaf turns a uniform pale yellow (starting from the older, lower leaves), iron chlorosis affects the newest growth first and leaves the veins green.

Most Susceptible DFW Turfgrasses

Soil Chemistry

Why Iron “Locks Up” in DFW Soil

Our local soils aren’t actually lacking iron. The problem is our high pH levels. DFW’s heavy clay and limestone bedrock create alkaline conditions (often pH 7.8 to 8.5).

When soil pH rises above 7.5, iron undergoes a chemical reaction that converts it into a solid, insoluble form. It’s there, but your grass simply cannot absorb it.

Go Deeper: The Chemistry
Iron is most available to plants in its ferrous (Fe2+) state. In high pH, oxygen-rich environments, it rapidly oxidizes into ferric (Fe3+) compounds, essentially turning into rust, which roots cannot readily take up. Lowering soil pH is the permanent fix, but extremely difficult in highly buffered limestone soils.

Soil pH & Iron Availability

pH 6.5Ideal Range
pH 7.8 - 8.5
DFW Soil Range
(Iron Locked)

Which Iron Chelate Actually Works in DFW?

Not all iron supplements are created equal. Using the wrong one in high pH soil is a waste of money.

Chelate TypeEffective pH RangeVerdict for DFW
EDTA IronUp to pH 6.5 Ineffective
DTPA IronUp to pH 7.5 Marginal
EDDHA IronUp to pH 9.0+ Best for DFW

Note: Foliar applications can bypass the soil entirely, but provide only temporary relief.

Stop Guessing. Get a Professional Soil Assessment.

Let our experts test your soil, diagnose the exact cause of your turf decline, and build a custom treatment plan.

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