DAP or NPK is used while planting. These fertilizers are quickly and are immediately available to the plants depending on them to provide essential nourishment in the form of nitrogen, phosphorus and potassium. DAP Aand NPK fertilizers have a distinct advantage over organic choices, which depend on soil organisms to first break down the organic matter before nutrients can be released. DAP and NPK are offered as dry granulesa and water-soluble powders. Controlled-release of these fertilizers dispense plant nutrients over an extended period from three to eight months, eliminating the need for repeated fertilizer applications throughout the growing season.