A chemical compound with the chemical formula KNO3 is potassium nitrate. It is an ionic salt of K+ potassium ions and NO3-nitrate ions, and is also a nitrate of alkali metals. Growers of high-value vegetable and orchard crops sometime prefer to use a nitrate-based source of nutrition. Potassium nitrate contains a relatively high proportion of K, with an N to K ratio of approximately one to three. Many crops have high K demands and can remove as much or more K than N at harvest. To support healthy growth, farmers often apply KNO₃ to soil or through the irrigation system during the growing season. The relatively high solubility of KNO allows for a more concentrated solution than for other common K fertilizers. It's easy to handle and apply, and is compatible with many other fertilizers, including specialty fertilizers for many high- Value specialty crops.