- Nitrogenous Fertilizers: (a) Nitrate fertilizers contain nitrogen in nitrate form; preferred by majority of plants, readily soluble in water and quickly available to plants. …
- Phosphate Fertilizers: Next to nitrogen, phosphorusis the most deficient primary nutrient element in Indian soils: …
- Potassic Fertilizers:
The “N” listed on commercial chemical fertilizers stands for nitrogen. Nitrogen is a structural component of proteins, DNA and enzymes, essential for the healthy growth and development of plants. To create most nitrogen chemical fertilizers, anhydrous ammonium is first synthetically manufactured by reacting N2 and H2 using the Haber-Bosch technology, which requires extreme heat and pressure. Anhydrous ammonium is 82 percent nitrogen and must be used with extreme care, as it can damage eyes, skin and lungs. Other sources of nitrogen in chemical fertilizer include diammonium phosphate, ammonium nitrate, ammonium sulfate, calcium cyanamide, calcium nitrate and sodium nitrate. Chemical fertilizers high in nitrogen are commonly used as lawn fertilizers, as they produce lush green grass.
The “P” found on commercial chemical fertilizer labels is for phosphate, a phosphorus-containing compound and the anhydrous form of phosphoric acid. Large amounts of phosphorus are needed in soil because this element, like nitrogen, is a structural component of DNA and also has a role in energy storage and conversion. Common sources of phosphate in chemical fertilizers include single and triple superphosphate as well as monoammonium and diammonium phosphate. Chemical fertilizers with a high content of phosphate are used with young plants to aid development of stems and a strong root network. In addition, fruit and vegetable growers use phosphorus-containing fertilizers to increase yields.
The “K” denoted on commercial chemical fertilizers represents potash, a potassium compound required for many chemical reactions in plants. Synthetically manufactured sources of potassium found in chemical fertilizer include potassium chloride and potassium sulfate, also known as muiate and sulfate of potash, respectively, as well as potassium nitrate and potassium-magnesium sulfate. Like phosphorus, potassium-containing fertilizers stimulate the development of strong stems and root networks in growing plants, as well as promoting flower production, which can increase fruit and vegetable yields.
Secondary and Micronutrients
Although many chemical fertilizers contain primarily the three macronutrients, manufactured forms of secondary and micronutrients are also available commercially. The secondary nutrients, sulfur, magnesium and calcium, are no less vital to healthy plant growth, they are simply needed in smaller quantities than the macronutrients. For example, sulfur is an essential structural component of proteins, magnesium forms a key part of chlorophyll, and calcium promotes permeability of cell membranes. They are found in chemical types of fertilizer as calcium nitrate, magnesium oxide and ammonium sulfate. The essential micronutrients include iron, manganese, copper, zinc and boron, which can be found in synthetically derived chemical fertilizers as iron chelate, manganese sulfate, copper chelate, zinc sulfate and sodium borate.