Now is the time to boost the floral and fruit production from your rhododendron, azalea, holly, blueberries, blue-flowering Hydrangea, dogwood and other acid loving plants with an application of organic, slow-release Holly-tone. Espoma offers many other outstanding organic fertilizers for non-acidic plants such as roses, perennials, trees, tomatoes and other flowering shrubs. I love their helpful project sheets.