Bonsai Tree Care Guide: How to Grow a Bonsai Tree

Bonsai is the Japanese art form of creating a miniature garden. A bonsai tree is a miniature version of a wild tree cultivated to grow in a smaller environment than its full-grown counterparts (“bonsai” is a Japanese word meaning “potted plant”). Any tree can be cultivated and turned into a bonsai. These little trees also live as long as their full-grown counterparts—in Japan, there is a white pine bonsai that is more than 500 years old. It is not easy to grow a bonsai tree, and every small tree takes special care and attention.

Many bonsai species are grown as outdoor bonsai, though some bonsai, particularly tropical and subtropical trees, can grow as indoor plants. Below are some types of indoor bonsai trees:

1. 1. Evergreen trees: Evergreen bonsai trees will stay green year-round as they shed old leaves and grow new ones. Some popular evergreen bonsais are the money tree (Pachira aquatica), Hawaiian umbrella tree (Schefflera arboricola), juniper bonsai (Juniperus), sweet plum (Sageretia theezans), ginseng ficus (Ficus retusa), Golden Gate ficus (Ficus microcarpa), and the weeping fig (Ficus benjamina).
2. 2. Deciduous trees: Deciduous trees shed leaves in the fall, and some popular deciduous bonsai trees include the Chinese elm bonsai tree (Ulmus parvifolia) and Japanese maple bonsai (Acer palmatum).
3. 3. Succulents: Succulent plants have fleshy, small leaves. Some popular bonsai trees with succulent leaves are dwarf jade plant (Portulacaria afra) and jade plant (Crassula ovata).
4. 4. Flowering trees: Popular flowering bonsais include the Fukien tea bonsai (Carmona retusa), gardenia bonsai (Gardenia jasminoides), and snow rose bonsai (Serissa foetida). Some varieties of ficus trees also grow flowers.

You can grow a bonsai from seeds, though that will take three to five years before it produces leaves. You can also purchase certain bonsai varieties from a garden center or specialty store. Follow these instructions to ensure your bonsai thrives:

1. 1. Repot your bonsai tree to ensure growth. When you purchase a new bonsai, carefully remove the tree from the current pot, clear the dirt away from the root mass, and prune any root tips that curve upwards or any overly large roots. Pruning the roots will ensure that the bonsai doesn’t outgrow its new container. The remaining roots should be slender and long and close to the surface of the soil. Do not remove more than 25 percent of the roots.
2. 2. Cover the bonsai in soil. Generally, a bonsai grows best in specialized bonsai potting soil—a mixture of akadama (a type of clay), pumice, lava rock, compost, and fine gravel/grit that provides aeration and nutrients. Make sure the bonsai pot has drainage holes.
3. 3. Place your bonsai tree in direct sunlight. Bonsai trees need at least six hours of direct sunlight a day—though some varieties will require more light or more shade, so check the particular care instructions. Place the bonsai plant on a window sill where it will get plenty of direct sunlight.
4. 4. Water the bonsai tree every few days. Water the bonsai thoroughly so the excess water drains through the potholes and the root system is thoroughly soaked. Water the bonsai when the soil is slightly dry or completely dry, every one to three days. Overwatering can lead to root rot.

Every bonsai will have particular care instructions depending on the type of tree. Follow these general bonsai care instructions so your plant will thrive in an indoor environment year-round:

1. 1. Fertilize the bonsai tree during its growing season. Because a bonsai tree is pot-bound, it will quickly deplete the soil’s nutrients and need frequent fertilization. Fertilize with a specialized bonsai fertilizer every week or two during its growing season from early spring to fall. In the winter, decrease the fertilizer to once a month. A yellowing bonsai can signify a lack of nutrients.
2. 2. Give your bonsai tree humidity. Many trees cultivated for bonsai are tropical and subtropical breeds, so they require ample moisture. Place the bonsai next to a humidifier or mist it with a spray bottle throughout the day. You can also lay the bonsai on a humidity tray. Fill a tray with decorative pebbles and pour water onto the pebbles—as the water evaporates, it will provide humidity to the plant. Ensure the water does not touch the bottom of the pot, or else it will make the soil too soggy.
3. 3. Prune the tree from early spring to fall. During growing season, prune the branches and leaves to keep the tree compact and encourage new growth. Put a healing paste on the cut area of pruned branches to prevent disease.
4. 4. Shape your bonsai tree with wiring. Use aluminum and copper wire to shape and curve the tree’s branches to keep it compact. When the plant is dormant in the winter, wrap the stems with the wire and bend them to the shape in which you want them to grow. After the branches grow in the desired direction, carefully remove the wire so as not to scar the plant.
5. 5. Repot the bonsai plant every few years. Repot bonsai trees in a new pot that’s at least one inch wider, give the plant fresh soil, and prune the root ball. The frequency of repotting depends on the tree species. Repot young, fast-growing bonsai trees every year or two, and mature bonsai trees every three to five years.

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