QuestionsHow to growTrees and ShrubsFeedingtreating chlorosis with sulphate of iron 0 Vote Up Vote Down Susannah Spence asked 15 years ago An article recommended treating plants affected by cholorosis by using sulphate of iron. I have bought liquid sulphate of iron but need guidance as to the dilution rate. 1 Answers 0 Vote Up Vote Down Gerry Daly Staff answered 6 years ago Much depends on the concentration of sulphate of iron in the liquid. It should say on the packet. Use 10ml in 10 litres of water watered onto the soil to see how it goes. Plant do not need much iron.