-Gro All-Purpose Plant Food, 3 Lb. instantly feeds flowers, vegetables, trees, shrubs, and houseplants with a dual feeding action that nourishes through both roots and leaves. for use on all indoor and outdoor plants, this water-soluble formula contains important micro-nutrients that promote quick, beautiful results. The product is not to burn plants when used as directed, and its waterproof packaging makes it i for outdoor merchandising. It can be conveniently applied using either the -Gro Garden Feeder or watering cans, with feeding every two weeks for optimal growth and health.