Boxwood bonsai care

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Generally, Buxus is a genus of small evergreen shrubs, although many reach tree-like heights (depending on the variety).

Many varieties of Buxus can be found in nurseries, however, Common boxwood (Buxus sempervirens) seems to be the most common species. There are also other buxus varieties that can be used to make a bonsai: Japanese boxwood bonsai (Buxus microphylla) and Chinese boxwood bonsai (Buxus harlandii). (These links will provide you with all the bonsai care guidelines).

Buxus sempervirens is a hardy tree that produces small, shiny, leathery, light green leaves. The plant also produces tiny clusters of flowers and fruits. However, these are not very noticeable on the tree.

It has a light brown bark that has a slight rough texture. However, it is not as fissured as Chinese boxwood.

Do boxwoods make good bonsai?

With its small leaves and attractive bark, this Buxus species works best as a bonsai. Buxus sempervirens, the common box, is easy to train and is especially suitable for smaller bonsai (small or mame). In general habit and appearance, the Common box (B. sempervirens) is not very different from the Small-leaved or Japanese box (B. microphylla). But, the leaves are a little different: Japanese boxwood has rounded leaves and Common boxwood has pointy leaves. Chinese box (B. harlandii) can be used to make slightly bigger bonsai trees. Chinese boxwood also makes for a slightly better bonsai because of its attractive bark along with its small leaves. It is also very tolerant of somewhat warmer indoor temperatures.

Boxwood bonsai is a very strong tree that can withstand most adverse conditions, despite its slow growth. Additionally, Boxwood (Chinese and Japanese) can withstand shocks caused by sudden changes in its environment due to its adaptability. A boxwood tree is an ideal subject for making into a twin-trunked tree, and it can be grown with its roots over a rock. There are some bonsai growers who have some wonderful and very old boxwood bonsai trees.

Boxwood bonsai trees also add plenty of sparkle (because of their shiny leaves) when they are at their best condition and on display.

To make common boxwood bonsai even more interesting, add some dead-wood effects to the trunk. It is even possible to split trunks through to enhance this effect. This will compensate for the lack of pronounced fissured bark and add the illusion of age. Usually, such modifications are done by experienced bonsai growers. Most boxwood bonsai specimens are likely to be very ordinary looking, lacking any significant artistic appeal.

To make a really nice, appealing bonsai, you will have to invest a substantial amount of time and also need to have a decent amount of skills. Look for an old hedge from which you can take your bonsai material.

Read more about other bonsai trees species in : Types of bonsai tree

Best location to keep Boxwood bonsai tree

Can a boxwood bonsai be kept indoors?

It depends on the species of the boxwood you are growing. Common boxwood bonsai (unlike Chinese boxwood or Japanese boxwood – indoors all year) needs to be placed outdoors in a sunny or partially shaded location. However, you can try using grow lights (read how to use grow lights for bonsai for more details). It will need good ventilation. It should, however, be protected from strong winds.

How much sun does a boxwood bonsai need?

It is not necessary to keep boxwood bonsai in full sun as the tree can thrive in partial shade. However, it can be exposed to the morning or evening sun for 4-5 hours a day.

Can boxwoods take full sun?

It depends on the variety of boxwood. Common boxwood and Japanese boxwood can be kept in full sun. On the other hand, Chinese boxwood will appreciate a relatively cooler location and partial shade. However, Chinese boxwood can be placed outside in spring after the last frost. Winter damage is particularly prevalent on new growth.

What temperature should a boxwood bonsai be?

Common boxwood can tolerate temperatures as high as 95°F (35°C) and as low as -10°F(-23°C). However, when grown in a pot, these trees are tender. Hence, keep the bonsai protected from frost in winter. In winter months, you can keep it in a cold greenhouse or indoors where it will be protected but also receive enough sunlight. An ideal temperature range for the common boxwood bonsai can be 59°F to 68°F (15°C to 20°C).

There is also a tendency for some growers to consider this tree as an indoor bonsai tree due to its need of protection during the winter months.

IMP: Refer to do bonsai trees need sunlight for more indoor and outdoor bonsai location ideas. Also, refer sunlight requirements for indoor plants for more indoor gardening ideas.

Propagation of Boxwood bonsai tree

Common boxwood can be propagated through seeds and cuttings. Sow seeds early in the year in a cold frame. Maintain a temperature of 59°F (15°C). Germination should take place within 30-90 days.

You can even use lignified cuttings to propagate boxwood in late summer. The cutting should be planted in a cold frame or in an open space in a peat-sand mixture.

I would rather recommend buying your bonsai specimen or getting your bonsai material from a garden hedge.

Watering Boxwood bonsai tree

How often do you water boxwoods in pots?

Even though common boxwood is able to tolerate brief periods of dryness, water your bonsai thoroughly in summer. Water the bonsai when the soil feels a little dry to the touch. You can also mist the bonsai in summer.

You can use hard tap water for boxwood bonsai as it likes some lime in the soil.

In the months of winter, reduce the frequency of watering. Be absolutely sure to not overwater the bonsai, especially in winter.

Read watering bonsai tree (for immersion technique) and indoor bonsai tree care for more details.

Wiring Boxwood bonsai tree

Boxwoods generally have a very stiff growth habit (and they have very hard wood). They lack the “flow” a bonsai should have (especially in the case of mature trunks collected from the wild). On the bonsai, aim to achieve a “softer” and more “flowy” shape. For this, train the boxwood bonsai from very early stage.

Boxwood bonsai can be wired at any time of the year. If you are planning for extreme styles such as semi-cascade, wiring must start at a very early stage as the older trunks are hard and cannot be bent. The bark will certainly be damaged if such an attempt is made.

If you have acquired your bonsai material with a thick trunk from a hedge, you will not have the option of training the trunk. Also, the trunk will have somewhat parallel shape. The branches on the top of the trunk can be wired and carefully positioned to partially disguise the parallel trunk and give an illusion of a taper.

Wiring can be done on branches that are one to two years old. The older branches will need to be guyed down with suspended wiring.

If branches have not emerged in the desired positions, wire nearby branches up or down and then outwards as required.

Read : Detailed guide on How to wire a bonsai. This extensive guide includes all the wiring techniques and Do’s and Dont’s. It will also show you other bonsai training techniques which can be achieved without using wires.

Pruning Boxwood bonsai tree

When to prune Boxwood bonsai tree?

How to prune Boxwood bonsai tree?

The branches of boxwood can be pruned at any time of the year. In fact, it requires regular pruning of the foliage to get light into the inner branches to encourage back budding and to keep the shape compact.

After the basic shape of the bonsai tree has been established, branches and leaves can be pruned into cushion shapes.

As soon as six pairs of leaves have developed on a new shoot, cut back the new shoot to two to three pairs of leaves. (Approximately from 10 cm back to 2 cm).

Roots can be pruned in spring at the time of repotting.

Read how to prune a bonsai to know about the right technique of pruning and more about defoliating a bonsai tree.

Repotting Boxwood bonsai tree

When to repot Boxwood bonsai tree?

Boxwood bonsai trees can be repotted every 2-3 years in the spring or fall. It depends on the development of the roots.

Prune the roots to about half.

Growth is slow and trunk thickening is virtually nonexistent when roots are confined to the pot.

If you want to increase the thickness of the trunk of your boxwood bonsai, do not prune the roots and remove it from the pot and plant it in the garden. Doing this will allow it to grow more freely and significantly more vigorously. 1-2 years in the garden will give a fairly thick trunk.

Choose a pot that has a deep color. If you are choosing a glazed bonsai container, make sure it is not too glossy. Read how to choose a container for your bonsai for more details.

After repotting, water adequately and provide the bonsai with some shade for few weeks.

Use a free-draining bonsai soil mix. Unlike Chinese boxwood, this tree is not very picky about the soil. It can grow in both slightly acidic/alkaline or neutral soil.

You can also make a bonsai soil mix by mixing loam, sand and peat moss (2:2:1).

Please check out how to repot a bonsai to know everything about repotting and root pruning a bonsai.

Must Read: Bonsai Soil Recipes

Feeding Boxwood bonsai tree

Boxwood bonsai should be fertilized either with controlled release fertilizers or with liquid feeds.

A controlled release fertilizer will ensure the bonsai grows well without the need for supplementary feeding for a longer period of time (between 6 and 18 months depending on the fertilizer).

You can also use any general purpose liquid feed every week during the growing season.

Do not feed in the winter. In winter, common boxwood goes into complete dormancy (unlike Chinese boxwood).

Read more about bonsai fertilizer and its application. This will also give you more details on how to feed flowering bonsai trees.

Diseases and pest of Boxwood bonsai tree

If placed in a good spot with plenty of ventilation, common boxwood will be trouble-free. However, it can be attacked by pests such as boxwood psyllid, boxwood mite, boxwood leafminer, and scales. Apply the appropriate pesticide.

It can also be affected by boxwood blight and leaf spot diseases. Box blight will defoliate the tree quite rapidly. Remove and burn the infected parts of the tree and apply the appropriate fungicide.

In poorly-drained soils, root rot can also occur.

Sometimes caterpillars can also pose some issues. However, these will not be any problem as they can be removed by hand easily.

Why is my boxwood bonsai dying?

A number of factors can affect the health of your boxwood bonsai, including overwatering, frost exposure, acidic soil (for Chinese boxwood), pest and diseases, and extreme temperatures (for Chinese boxwood). Overwatering is one of the biggest factors in the death of a boxwood bonsai. Many bonsai growers make the mistake of watering the bonsai when the bonsai soil is moist. In spite of boxwood being a robust tree, it is hypersensitive to overwatering. Moreover, when grown in a pot, this plant is treated like a tender plant and hence should not be exposed to frost. Acidic soil can also prove to be detrimental to the health of your Chinese boxwood bonsai. It will reduce the availability of critical nutrients. Furthermore, in case you have a Chinese box bonsai, change the location of your bonsai. There may be a problem with it being exposed to the full sun for a long period of time. As boxwood can easily handle the shock of a new location, you don’t need to worry about acclimating the bonsai to the new location. Also, check for any symptom of pest and disease.

Please make sure you read our comprehensive guide: How to identify and treat bonsai pests and diseases is a great resource for you to see all the organic and inorganic remedies you can use.