Because of its high nitrogen content, ammonium nitrate is commonly used as a fertilizer. Nitrogen is a nutrient for plants and aids their essential growth and metabolic processes, increasing plant yield in the process. Nitrogen also helps in a plant's ability to photosynthesize.
While many varieties of fertilizer can be expensive for farmers to use regularly, ammonium nitrate, commonly sold in the form of pellets, provides a cheap yet effective alternative. However, in addition to being used in fertilizers, ammonium nitrate is also very reactant in heat and has application in explosives when paired with substances such as TNT. This fuel is called ANFO, or ammonium nitrate fuel oil.