The growth in plants is divided into three phases they are formation, elongation and maturation. In the first phase new cell formation is take place due to the activity of the apical meristem. Next is the phase of elongation in which the newly produced cell undergo enlargement and the deposition on the cell wall also found at this stage. In the phase of maturation the cell will try to attain a maximum of wall thickening and modification of the protoplasm also occurs. Plant growth rate is slow in the initial phase so called as the lag phase. The rapid increase in the rate of growth occurs at the second phase so it is known as log phase or exponential phase. In the third phase the rate of growth slowdowns and retain the size. This is known as the steady phase or stationary phase.