Uncertainty of monsoon rainfall: 80% of rainfall in India is received during monsoon period. Monsoon rainfall is very uncertain. So irrigation is very important to supply water to plants also and when needed.

• Uncertainty of monsoon rainfall: 80% of rainfall in India is received during monsoon period. Monsoon rainfall is very uncertain. So irrigation is very important to supply water to plants also and when needed.
• Uneven distribution of rainfall: To compensate the uneven distribution in an area, supplemental irrigation is needed.
• Effect of winter rainfall (N India)/ Effect of SWM in S. India: Supplemental irrigation is inevitable in the regions due to poor rainfall.
• Cultivation of high yielding crops: High yielding crops produce heavy biomass and economic yield. Higher biomass need more water for its production. Hence supplementation of water as irrigation is essential.
• Difference in water holding capacity of the soil: Sandy soil - low WHC – frequent irrigation. Clay soil - high WHC - frequency is less.

Uneven distribution of rainfall: To compensate the uneven distribution in an area, supplemental irrigation is needed.

Effect of winter rainfall (N India)/ Effect of SWM in S. India: Supplemental irrigation is inevitable in the regions due to poor rainfall.

Cultivation of high yielding crops: High yielding crops produce heavy biomass and economic yield. Higher biomass need more water for its production. Hence supplementation of water as irrigation is essential.

Difference in water holding capacity of the soil: Sandy soil - low WHC – frequent irrigation. Clay soil - high WHC - frequency is less.