Holly-tone is the original plant food for all acid loving plants like azaleas, rhododendrons & evergreens. Holly-tone's all natural formula contains Bio-tone, the proprietary blend of beneficial microbes. Bio-tone biologically enhances the natural plant food to ensure superior plant growth. The leading choice for hollies, azaleas, evergreens. rhododendron and other acid loving plantsComplex blend of natural organicsEnhanced with Bio-tone microbes for optimum growth and bloomsProvides Elemental Sulfur to help maintain soil acidityEnvironmentally friendlyNo sludge, hazardous or toxic ingredientsLong lasting, slow releaseWon't burn or leach awayContains organic matter rich in vitamins and beneficial microbes to improve soil