Grains are a staple of human diets. The global abundance of these nutritious foodstuffs depends on agronomic sciences, which have the know-how to develop high-yielding, stress-tolerant varieties and the methods to create a suitable environment for crop growth by managing fields and agricultural inputs sustainably. Once the agronomist has optimized plant access to sunlight and water in a non-compacted soil and controlled the weeds, diseases, and pests that could limit crop growth, their attention turns to a responsible nutrient management program. Soil testing and analysis allows the agronomist to estimate how much of the 14 essential plant nutrients – nitrogen (N), phosphorus (P), potassium (K), sulfur, calcium, magnesium, iron, boron, manganese, copper, zinc, molybdenum, nickel, and chlorine – will be supplied by natural soil fertility, and which nutrients may need to be added. Agronomists may advise the use of inorganic fertilizer if it is a convenient and cost-effective choice for the cropping system. Inorganic fertilizers are typically water-soluble salts formulated as solid granules, liquid solution (e.g. urea ammonium nitrate), or high-pressure gas (e.g. anhydrous ammonia). The most common are the solid fertilizer granules that supply a single nutrient or a mixture of nutrients. Inorganic fertilizers are nutrient-dense with a higher guaranteed analysis than organic fertilizers, which are typically rated around 1‒1‒1, meaning 1% by dry weight of N, 1% of P in the form of P2O5 and 1% K on the basis of K2O. The physical and chemical properties of inorganic fertilizers makes it easy to apply them at the right depth and distance from the seed or growing plant, at a suitable time in the growing season. Consequently, inorganic fertilizers are applied to supplement the natural soil fertility and increase the growth of grains and other agricultural plants, including vegetables, perennial hayfield, vine, and tree crops.