Bonsai is achieved by the confinement of the tree in a pot. The size of the tree will depend on the size of the pot. Mame bonsai are so small that the pot can have the diameter of a quarter! Repotting not only provides the tree with the chance to stay small, but also to grow larger. If it is desired that the tree grow larger, a pot’s length, that is two-thirds the height of the tree is recommended. The primary reason that one repots is not only to give the tree a new home, but also new soil. Watering leaches out the minerals and nutrients that the soil provides. There are many bonsai soil mixes on the market but many bonsaists like to make their own. Repotting also provides the opportunity to prune the roots but this does not have to be done every time one repots, especially if the tree is moving into a larger training pot. Repotting is usually done every year on young trees and every two to three years on older trees. Illustrated below is the process of repotting: