NPK (nitrogen, phosphorus, and potassium) are the main ingredients in most fertilizers. The letters NPK stand for the three major nutrients that plants need to live and grow – nitrogen, phosphorus, and potassium. Plants need other nutrients like iron, calcium, and even chlorine, but N, P, and K are the big three. How plants respond when fertilized depends largely on the ratio between the three elements (N-P-K). To obtain the ratio, divide all three numbers on the label by the smallest number. Examples: 20-20-20 fertilizer has a 1-1-1 ratio 15-30-15 fertilizer has a 1-2-1 ratio 10-5-5 fertilizer has a 2-1-1 ratio When choosing fertilizer, it is very important to check its ratio. For instance, to encourage plants to root, you need to choose a fertilizer that is higher in phosphorous than in nitrogen or potassium, i.e. one with a 1-2-1 ratio. The following are the main fertilizer ratios used by gardeners: Rooting: 1-2-1 Flowering and fruiting: 1-1-2, 1-2-2, 2-1-2 All-purpose: 1-1-1 Leafy growth: 2-1-1, 3-1-1 N.B.: Although natural fertilizers often have different ratios from these ones, they are no less effective. Packaging: In bulk or bags / 25KG / 50 KG