Fish, Blood & Bone Natural Feed For A Healthy Garden 5 Weeks Nutrient Release Rich In Trace Elements For Stronger Plants Easy, Ready To Use Granules Ideal For Flowers, Fruit, Trees, Shrubs & Vegetables Westland Fish, Blood and Bone is a good natural source of all three of the major nutrients. Potassium to support flowering, Nitrogen to support green growth, Calcium keeps your plant healtyh & strong & Phosphorus to allow roots to grow bigger & stronger This is a naturally sourced feed Nutrients are taken up efficiently due to longer period of release in the soil.