The repotting process is an essential part of the bonsai growing process. Bonsai trees require repotting when they have outgrown their containers. Repotting the bonsai is also a preventative measure, helping to prevent development of bound root systems and increasing nutrient intake.
Select a planting container for the bonsai. Choose a container that is slightly larger than the original and that includes a drainage system. Place the container in close proximity to the area in which the repotting process will be completed.
Prune away any damaged, dying or wilted branches and stems from the tree. Cut away any spent flowers. Begin the repotting process in the early spring, just before the growing season begins.
Gently remove the bonsai plant from its container and lay it onto a table. Remove any excess soil from the root system. Gently untangle and spread out the bound root system using a root comb. Pay close attention to the condition and healthiness of the system.
Prune the root system of the bonsai tree. Trim away no more than a third of the bonsai's root system. Avoid excessive root pruning to avoid dieback or growth stunt. Use sharp, sterile scissors to complete this process.
Cover the drainage holes of the new potting container with mesh coverings. Wire the coverings into the hole to maintain their position. Line the bottom of the container with a layer of soil. Place the bonsai in the center of the container and fill the container with the remaining soil.
Use a nutrient-rich soil that promotes moisture and is well drained. Use a combination of nutrient soil, compost and sand. Combine the ingredients in equal parts, incorporating thoroughly before beginning the repotting process.
Water the tree according to the tree variety. Some bonsai trees, such as jade, cactus and other succulents, do not require immediate watering after repotting. Wait several days before watering. Other bonsai varieties, such as maple, juniper and ficus, will require immediate watering after repotting. Water lightly and check the soil's moisture the following day for any additional watering requirements.
Avoid fertilizer applications for at least two weeks after the repotting process is completed. The bonsai tree will need some time to reestablish itself to the new container. Place the newly repotted bonsai tree in a partially shaded area that receives at least four to six hours of daily morning sunlight.