Phosphorus is the macronutrient that encourages strong root growth, and it plays a key role in photosynthesis. Bone meal is a terrific source of phosphorus, and an very useful when planting flower bulbs and getting transplants established. Orgunique Bone Meal Plus is a good source of phosphorus and calcium. It is composed of fish bone meal, rock phosphate, and humic acid derivatives. This easy-grip canister contains enough granular fertilizer to treat 10m2 (100 square feet) of bed. 1.5kg.