Holly-Tone organic fertilizer is for acid-loving plants, such as hollies, azaleas, camellias, evergreens, hydrangeas, dogwoods, blueberries, strawberries and rhododendrons. It is rich in natural organics and used and recommended by Professionals for decades. Holly-Tone also contains Bio-tone, our proprietary blend of beneficial microbes. Bio-tone biologically enhances our organic fertilizer to ensure great plant growth.