EDTA is a powerful, synthetic amino acid that functions as a chelating agent. The term “chelate” comes from the Greek word chele, meaning “claw.” This analogy perfectly describes how EDTA works: it forms a stable, cage-like structure around metal ions, such as zinc (Zn), manganese (Mn), and copper (Cu).
The primary use of EDTA chelates is to deliver essential micronutrients to plants effectively. While plants require macronutrients (N, P, K) in large amounts, micronutrients are just as vital for key biological processes like photosynthesis, enzyme activation, and overall growth.
EDTA chelates are applied through:
➊ Soil Fertilization: Mixing with soil to provide a steady release of nutrients.
➋ Foliar Spray: Applying directly to the leaves for rapid absorption.
➌ Hydroponics/Fertigation: Dissolving in irrigation water or nutrient solutions.
They are an indispensable solution for preventing and correcting micronutrient deficiencies, which manifest as conditions like chlorosis (yellowing of leaves) and stunted growth, common in calcareous or high-pH soils.
The efficacy of EDTA lies in its ability to protect micronutrients.
In many soils, especially those with alkaline (pH>7) or high-phosphate content, essential metal micronutrients naturally react with soil compounds. This reaction renders them insoluble and “locked up,” making them unavailable for the plant’s roots to absorb.
EDTA binds the micronutrient (e.g. Zn2+), forming a stable, water-soluble complex. This bond prevents the metal ion from reacting with soil minerals and becoming insoluble.
