Iron-Based Herbicides: How Chelated Iron Kills Broadleaf Weeds Selectively

Several organic weed killers use chelated iron (FeHEDTA) as the active ingredient. Products like Ortho Elementals, Natria, and Fiesta exploit the different iron-uptake mechanisms of broadleaf weeds (dicots) versus turfgrasses (monocots). The iron overload causes oxidative damage and necrosis in broadleaf weeds while leaving grass unharmed. In practice, these products provide effective selective control of broadleaf weeds in lawns.