The supply of water to crops at right time is called irrigation. All the crop plants need water for their growth. Water is important for proper growth and development of flowers, fruits and seeds of plants.

Irrigation is necessary for the absorption of nutrients by plants from the soil. Water is absorbed by the plant roots. Along with water, minerals and fertilizers are also absorbed.

Irrigation is necessary to provide moisture for gemination of seeds because germination of seeds does not take place under dry conditions.

Irrigation is also necessary for healthy crop growth so as to get good yield. Nutrients dissolved in water get transported to each part of the plant. Water also protects the crop from both frost and hot air currents.