The normal growth of plants needs 16 essential elements and 6 macro elements: carbon, hydrogen, oxygen, nitrogen, phosphorus and potassium. Three medium elements: calcium, magnesium and sulfur; Seven trace elements: iron, zinc, manganese, copper, boron, molybdenum and chlorine.

Plant essential elements are indispensable nutrients for any crop at any growth and development stage. In addition to the essential elements for plants, there are some beneficial elements, such as silicon, sodium, nickel, cobalt and vanadium, which are necessary for some crops under certain conditions. The shortage and surplus of plant nutrients are not conducive to plant growth. The lack of essential elements in plants will affect the normal growth of plants; Too many essential elements in one plant will lead to insufficient essential elements in other plants, so it is as important to balance the proportion of essential elements in various plants as it is to have enough essential elements in one plant. The application of this concept in practice is the balanced fertilization method. Various plant essential elements should circulate between plants and soil minerals and soil organic matter. The cycle of nitrogen and sulfur also involves the atmosphere. The supply of essential elements in plants should be balanced with demand and consumption. The purpose of applying various fertilizers is to maintain nutrient balance.