Maintaining a healthy bonsai tree is a relatively simple process. The tree will require regular attention and occasional preventative measures. When the tree receives a good balance of these requirements, your tree will thrive for many years to come.
Repot your bonsai every one to two years. If the bonsai begins to show signs of dieback or stunted growth, the bonsai requires repotting. It will also require repotting when the roots begin to bulge from the sides of its potting container. Complete the repotting during the early spring months, right before the bonsai's growing season. When repotting, make sure to remove the excess soil from the roots and trim them back approximately one third of the way. Quickly repot the plant to avoid drying roots.
Develop a watering schedule that meets the needs of your tree and water it at the same time each day. Bonsais require regular watering but cannot tolerate overwatering and wet feet. Check the bonsai's soil moisture before each watering. If the soil feels dry about an inch from the surface, the bonsai requires watering. Every bonsai has its own watering requirements, which are primarily based on its environment. Therefore, make sure that the provided watering schedule meets the tree's individual needs. Additionally, ensure that the bonsai's potting container has an ample drainage system that allows the excess water to exit the pot.
Place your indoor bonsai tree in an area that receives at least four hours of direct sunlight each day. Bonsai trees are sun loving plants that require ample amounts of sun. While outdoor bonsai trees need at least six to eight hours of sun each day, indoor bonsais adapt to the limited sunlight. Still, the bonsai requires a combination of sunlight and water to create its essential nutrients. Indoor trees should be placed in a well lit area that obtains a great amount of morning sunlight to avoid the potential burn of the evening sun.
Maintain a humid environment for your bonsai. These trees thrive best in humid areas. Indoor environments usually have very dry air. Counteract the dry air by misting your tree's foliage several times each day. The bonsai will benefit from the extra moisture. Humidity levels can also be maintained by placing the tree on a humidity tree or centering a small fan by the tree to circulate the air.
Fertilize your bonsai tree regularly throughout its growing season. Generally, the bonsai will experience its growing season from early spring through late fall. Fertilize the tree monthly throughout this season with a well balanced fertilizer. The fertilizer should contain equal amounts of potassium, phosphorous and nitrogen, and should be used at half strength.