Pro Holly is an excellent fertilizer for acid loving shrubs. On our gardening crews, we mix it with Penobscot Blend compost and feed this category of shrubs every spring.
We love North Country Organics fertilizer blends! This what they say about Pro Holly:
"PRO-HOLLY 4-6-4 is a natural fertilizer blended from mineral and organic ingredients specifically made for ericaceous/acid loving plants such as: Azaleas, Blueberries, Chrysanthemums, Ferns, Gardenias, Rhododendrons, Heaths, Heathers, Huckleberries, Hydrangeas, Marigolds, Mountain Laurels, Oak trees, Pachysandras, Lupine, Raspberries, Yews, Flax, and other acid loving plants."