Medium- and Micronutrient Fertilizers

Medium- and micronutrient fertilizers is a general term for compound fertilizers produced by combining medium-nutrient elements and micronutrients. The full name is “compound fertilizer containing medium- and micronutrients.”
Introduction to Nutrients: Major Nutrients, Medium Nutrients, Micronutrients, and Beneficial Elements
(I) Major Nutrients Required by Crops
Carbon (C), Hydrogen (H), Oxygen (O), Nitrogen (N), Phosphorus (P), Potassium (K). Carbon, hydrogen, and oxygen can be obtained from the air and water. Among these, crops require large amounts of nitrogen, phosphorus, and potassium, but soil supplies are often insufficient. Fertilization is frequently necessary to meet crop growth requirements; therefore, nitrogen, phosphorus, and potassium are referred to as the three essential nutrients for crops or the three essential elements of fertilizers.
(2) Secondary Nutrients Required by Crops
Calcium (Ca), Magnesium (Mg), Sulfur (S)
(3) Micronutrients Required by Crops
Iron (Fe), Zinc (Zn), Manganese (Mn), Copper (Cu), Molybdenum (Mo), Boron (B), Chlorine (Cl)
(IV) Beneficial Nutrients Required by Crops
Sodium (Na), Silicon (Si), Cobalt (Co), Selenium (Se), Iodine (I), Vanadium (V), Titanium (Ti)
(V) Relationships Among Various Nutrients Required by Crops
Essential nutrients are equally important in crops regardless of their quantity; the specific physiological and biochemical functions of any single nutrient cannot be replaced by other elements. This principle is known as the law of equal importance and irreplaceability of crop nutrients. However, certain elements with similar chemical properties and functions can partially substitute for one another; for example, boron can partially alleviate iron deficiency symptoms in flax, and sodium can partially satisfy sugar beets’ potassium requirements.

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