Which nitrogen compounds are commonly used in fertilizers?

Nitrogen compounds are essential components of modern synthetic fertilizers, as nitrogen is a primary nutrient required for plant growth. Most of these fertilizers are derived from synthetic ammonia (NH₃), which is produced via the Haber-Bosch process.1234

Common nitrogen compounds used in fertilizers include:

• Urea: One of the most concentrated nitrogenous fertilizers, it is highly valued because of its high nitrogen content and its ability to be readily converted to ammonia in the soil. It can be applied alone or incorporated into mixed fertilizers.15
• Ammonium salts: Ammonia is frequently converted into various salts, including ammonium nitrate, ammonium sulfate, and ammonium phosphate.13
• Nitrates: Compounds such as sodium nitrate and potassium nitrate are also utilized as nitrogen sources.2

Additionally, nitric acid is a key commercial compound used in the production of fertilizers, particularly in the manufacture of ammonium nitrate. In the soil, plants primarily absorb nitrogen in the form of nitrate or ammonium ions.643