Types of Fertilisers: Urea, DAP, NPK, Water-Soluble and Micronutrients Choosing a fertilizer is not simply a matter of buying the most familiar bag or selecting the product with the highest nutrient number. Urea, DAP, NPK fertilisers, water-soluble fertilisers and micronutrient products perform different functions. The right choice depends on what the soil can already supply, what the crop needs, its growth stage, the irrigation system and the intended application method. No