Chelated Iron DTPA (Fe-DTPA) is a water-soluble micronutrient fertilizer in which iron (Fe) is chelated (bound) with DTPA. This chelation protects iron from reacting with other elements in the soil, especially in neutral to moderately alkaline conditions, keeping it available for plant uptake. Fe-DTPA typically contains 11% iron and is commonly used to prevent or correct iron deficiency (chlorosis) in a wide range of crops.