Scotts® MossEx™Scotts MossEx controls moss without harming your lawn. After you apply MossEx it will attack undesirable moss, causing it to turn black and disappear. It also contains nutrients to green your lawn and develop thick grass. Apply Scotts MossEx in the winter or spring when moss is actively growing. It is best applied when the lawn is moist and tall grass has been mowed to expose low growing moss. We recommend using a Scotts spreader to apply this