The necessity of osmosis in plant life is unlimited. A short description of this is given below:
Absorption of water: Plant absorbs water by root hairs in the process of osmosis.
Movement of water: Water moves inside the plant body by cell-to-cell of osmosis.
Opening and closing of stomata: Opening and closing of stomata are controlled by osmosis. So osmosis also controls the rate of transpiration.
Swelling and growth of cell: For normal growth and expansion of the cell it needs to swell. Cells become expanded by absorbing water through osmosis. This osmosis plays an important role in the growth of the cell and maintains its normal shape and size.
Equal distribution of water: Water is essential for almost all the organic activities. These activities are going on in the living cells. Osmosis is very active to reach water to every living cell from root to leaf.
Turgidity of the cell: Soft cells become turgid by absorbing water. Cell absorbs water by osmosis.
Germination of seeds: The success of germination depends on the process of osmosis.