"Liquid solutions" or "clear liquid fertilizers" or are fluid fertilizers in which all nutrients have been completely dissolved in solution. They are prepared by dissolving water-soluble fertilizers and are applied as solutions. Solution fertilizers are especially well adapted to application through microirrigation systems, as they are clear and contain few sediments or impurities. Liquid solutions can also be banded or sprayed on soil beds.
NPK solutions are factory-prepared as liquid fertilizer mixes of various grades and NPK ratios; for example, 1:2:2 (5-10-10) and 3:2:1 (12-8-4). The farmer can also mix fertilizers in the field and prepare liquid NPK stock solutions with relatively low nutrient concentration, and then apply them through the irrigation system (fertigation).