EDTA chelated iron (EDTA-Fe, full name: Ethylenediaminetetraacetic Acid Ferric Sodium) is the most widely used chelated micronutrient fertilizer in agriculture. With CAS No. 15708-41-5 and molecular formula C₁₀H₁₂FeN₂NaO₈, it contains approximately 13% elemental iron and appears as a pale yellow to brownish-yellow soluble powder.

Its core structure features an EDTA chelating agent molecule that acts like a "molecular claw", tightly wrapping the iron ion inside to form a stable cyclic chelate. This structure protects iron ions from reacting with carbonate, phosphate and calcium ions in soil to form insoluble precipitates, keeping iron in a water-soluble active state that can be directly absorbed by crop roots and leaves.

EDTA chelated iron adapts to soil environments with pH 4.0-7.0 and performs best in acidic to neutral soils. It is widely applicable to field crops, fruits and vegetables, horticultural flowers and hydroponic systems, serving as an efficient iron supplement for correcting iron deficiency chlorosis in crops.