Espoma Organic Berry-tone Natural Organic Fruit & Berry Fertilizer is a plant food designed specifically for fruits and berries. For bigger fruit and growth. Long lasting, slow release. Ideal for all blueberries, strawberries and raspberries. 100% natural and organic approved plant foods. The Tone products are made for complex blends of the finest natural and organic ingredients. No sludges or fillers are ever used. They are enhanced with Bio-Tone beneficial microbes to help plants establish fast, develop deeper roots and have superior blooms. Long lasting results - won't burn or leach away.