FoxFarm Happy Frog Acid Loving Plants Fertilizer 4 lb bag. Rhododendrons, azaleas, hydrangeas, and other acid-loving plants have special nutritional needs. FoxFarm's Acid Loving Plants Fertilizer provides gentle slow-release nutrition for plants that require a low pH. Happy Frog Acid Loving Plants Fertilizer is specifically formulated for use on azaleas, rhododendrons, camellias, hydrangeas, evergreens, blueberries, raspberries, strawberries, and all other acid-loving plants. This blend of fertilizers and microorganisms delivers nutrition where your plants need it most. Mycorrhizal fungi are included to help increase root efficiency, which may enhance nutrient uptake and water absorption. OMRI Listed. NPK: 4-5-3.