The growth of crops for which they are suitable for soil nutrients nutrients it says. An average of 16 nutrients are required for good growth of any crop . These 16 nutrients are divided into three groups.
1) Main food: -
Nitrogen, Phosphorus and Potash are the major nutrients required by the crops which are obtained from the soil and manure.
Carbon, hydrogen and oxygen are also essential elements for plant growth. They get what is supplied to them through air and water.
2) Secondary nutrients: -
Calcium, Magnesium, Sulfur are the nutrient crops required in moderation. They are also supplied to the crops from the soil.
3) Micronutrients: -
Crops also need nutrients like iron, manganese, copper, zinc, molybdenum, boron, chlorine, but this requirement is very low.