Aluminum Sulfate Granular FertilizerGreat for HydrangeasAcidifies Soil (lowers pH), corrects high alkalinityContains: Fertilizer grade Aluminum Sulfate, as Metallic 9.0%. Not for spray application.Use on: Acid loving shrubs like rhododendrons, hydrangeas, blueberries, dogwoods, holly, gardenias, camellias, and azaleas.Corrects: Excess alkalinity in the soil.Rate: For large shrubs use 1 lb. per 3 ft. of height. For Trees, use 1 lb. per inch of trunk diameter. For small shrubs, use 5 lbs. per 100 sq. ft.Application: Broadcast evenly, wash off foliage and water.