500g Iron Sulphate heptahydrate 99% pure•LAWN FERTILISER•LAWN GREEN•
Test a small area with a 1% Ferrous Sulphate Heptahydrate solution (ie. 10gms/1L of water). If this does not give the desired effect a stronger solution can be used up to a maximum of 5% Ferrous Sulphate Heptahydrate (50gms/1L of water ).