Maxicrop's Lawn Tonic and Moss Killer is a natural seaweed extract with added ferrous sulphate. For use only as a home garden lawn treatment. Simply mix with water in a watering can or sprayer. The liquid application saturates moss and kills it quickly and efficiently, while the seaweed extract tonic encourages grass re-growth, improves rooting and ?greens up? the grass. Size: 500 ml.