Bone meal is often a by-product through the animal processing industry and also the animal bones are washed and ground into a powdered kind. Bone food is very low in nitrogen and potassium but really high in phosphorus. For perennial plants, the timing is dependent upon the plant’s growth cycle. https://byd03579.blogscribble.com/29535354/considerations-to-know-about-fertilizer-for-leafy-greens