How often should bonsai pieces be repotted?
Repotting may be done as often as every year, but for older specimens, the interval may be as long as five years. Older trees need less frequent repotting; the goal is to maintain their existing proportions, with moderate growth. Bonsai specimens are repotted to refresh a portion of the soil and to renew the vigor of the plant, not to produce a noticeable increase in size.
