The Ultimate Care Guide For Boxwood Bonsai Trees

Boxwood bonsai is a great choice, whether you’re looking for a beginner bonsai tree or something to add variety to your collection. They’re very flexible, they can be styled in many different ways, and they’ll grow well as either indoor or outdoor trees.

If you’re looking to learn about boxwood bonsai, then this is the guide for you. I’ll explain all the important information about how to care for them, how to prune and style them, and where you can buy quality boxwood bonsai.

What is Boxwood?

Boxwood is an evergreen plant with dark green leaves and small white flowers that bloom in the spring. The boxwood tree can grow to be up to 60 feet tall. However, when grown as a bonsai, it remains small enough to fit in a pot on a windowsill or coffee table.

While it’s often used as an ornamental plant in landscaping, boxwood can be trained into many different sizes and shapes of bonsai trees.

Popular Varieties of Boxwood:

There are over 200 varieties of boxwood bonsai that can be grown both indoors and outdoors. The most common types of boxwood bonsai include:

Buxus microphylla (Japanese Boxwood):

Buxus microphylla is the most popular variety of boxwood. It grows up to 2 feet per year, has small leaves, and retains its rich green color in the winter months.

They can be used for hedges, borders, screens, topiaries, bonsai, and more. In warmer climates, it can also be used as a foundation plant or groundcover.

One type of Buxus microphylla that is particularly popular is Winter Gem, which retains its deep green color in the winter months thanks to less chlorophyll production when temperatures drop.

Buxus harlandii (Chinese Boxwood):

It is similar to Buxus microphylla but has a more upright form. It grows well in zones 7 through 9 (average minimum winter temperature of 0 to 20 degrees Fahrenheit).

Buxus sempervirens (European Common Boxwood):

Buxus sempervirens is the most cold-hardy of all boxwoods. It can tolerate temperatures down to minus 20 degrees Fahrenheit (zone 5).

Why Grow Boxwood Bonsai:

boxwood bonsai tree
  • You can grow boxwood bonsai both indoors and outdoors, though some people find them easier to work with outdoors. Regardless, they’re an ideal choice for people who want a relatively easy-to-care-for bonsai tree.
  • Boxwoods are low-maintenance trees that can thrive in almost any condition.
  • Boxwoods also happen to be one of the best choices for beginner bonsai growers because they’re so hardy, forgiving, and long-lived.
  • These trees are also great for creating hedge-style bonsai gardens because their dense foliage makes them look like miniature hedges.
  • They’re easy to train with wire, prune and shape.
  • They look great all year round and can live for many years. Some boxwood bonsai trees have lived for more than 100 years!

Boxwood Bonsai Care Guide

How Often Should I Water Boxwood Bonsai?

Boxwood bonsai should be watered when the top of the soil feels dry. You probably won’t need to water every day if you have them indoors; once every one or two days is enough.

If you have them outside and the weather is hot and sunny, then you may need to water them more often – up to twice per day.

When watering your tree, make sure that the water penetrates deep into the pot; place it in a sink and let it soak for a few minutes before moving it back into position.

Bottom-Watering Boxwood Bonsai:

When you have a boxwood bonsai tree, the best way to water it is from the bottom up. Your bonsai tree is not only beautiful, but it is also very fragile.

Bottom-watering is a common way of watering plants, usually done when the soil is dry.

To do this put the bonsai pot in a tray filled with water for about 15 minutes until the soil absorbs enough water.

Bottom-watering preserves the beauty and health of your tree while not affecting its roots.

Can You Grow Boxwood Bonsai Indoors?

The answer to this question is a tricky one — it depends on the species of boxwood you have.

Generally, boxwood bonsai trees can be grown successfully indoors with the right light, air and water conditions. If you plan to grow a boxwood bonsai indoors, place it in a window that gets bright, indirect light.

But remember there are over 70 different species in the genus, and they have different needs.

Japanese boxwood (Buxus microphylla) is the most common choice for indoor bonsai. It’s hardy, can grow in low light conditions, and can survive periods of neglect for beginners who are still learning the ropes.

English boxwood (Buxus sempervirens) is on the other hand not the best choice for a beginner. It’s more sensitive to changes in temperature, humidity, and light exposure than other types of boxwood. However, it grows well indoors when cared for properly.

How Much Light Do Boxwood Bonsai Need?

Boxwood bonsai trees do well in full sun, especially if the soil is kept moist.

Younger Boxwoods should be kept in bright light, but not direct sunlight. In summer they can be kept outside in the dappled shade, or a place where they get some sun in the morning and some in the evening, but none during the middle of the day when the sun is at its hottest and most intense.

Once they’ve grown a bit, move them into full sun. Mature boxwoods can tolerate full sun without any problems.

When it’s hot outside, make sure your boxwood gets enough water so it doesn’t dry out in the heat. Brought them inside during the winter months since it won’t tolerate cold temperatures below about forty degrees Fahrenheit.

If you’re struggling to provide enough sunlight indoors, supplementing with strong artificial lighting may help. Remember that artificial lighting isn’t just for indoor cultivation — they’re ideal for patio growing as well.

How Do You Prune Boxwood Bonsai?

Pruning is one of the most important parts of the process when it comes to boxwood bonsai trees. You should prune your boxwood bonsai tree at least once every three months to encourage new growth and keep it looking neat and trimmed.

Use sharp scissors or pruning shears for this job.

Cut off any overgrown or damaged branches, or branches that cross each other. Make angled cuts above leaf nodes so new growth will appear there to fill in the tree’s shape.

Be sure to disinfect your cutting tools between uses with a 10 percent bleach solution.

Shaping Boxwood Bonsai

The first time you trim your boxwood bonsai, it’s important to do it right. It takes time and patience, but the end result is worth it.

The best way to go about trimming your boxwood is by following a shaping guide. This will allow you to shape your tree correctly and get good results.

Do not cut too much off at once because that can easily ruin a perfectly good bonsai. Instead, work on one side of the tree at a time and gradually give it its desired shape.

Trim the tree in stages, starting with its top branches. You should then move to the middle of the tree and finally, its bottom branches. Take your time when trimming or you could damage or even kill your tree.

When trimmed regularly, boxwood bonsai trees will develop a dense canopy that can be manipulated into almost any shape imaginable.

Can You Defoliate Boxwood Bonsai?

It is possible to defoliate boxwood bonsai, but it is not recommended. The reason for this is simple. Boxwood bonsai would lose a large part of their energy reserves and would need a lot of time to recover from it.

The only reason you should consider defoliating your boxwood bonsai is if you want to reduce the size of its leaves.

Defoliation is a process where all the leaves are removed to create a smaller leaf size. The new growth will be smaller than the old and will take on the bonsai look. This can be stressful and is best done in early June so your tree can fully recover before winter. 

Defoliate on a warm, dry day in early spring while the plant is still dormant but just beginning to bud out. This will give it enough time to produce new leaves before summer heat sets in.

If you defoliate when the plant is actively growing, it could stress the plant and kill it or cause damage that could take years to recover from

Defoliation is not common in bonsai and should only be practiced by experienced growers.

How Often Should I Repot Boxwood Bonsai?

Boxwood bonsai trees do well in small pots, which means you don’t have to repot very often. When you do repot them, make sure it’s late in the summer or early fall when the roots are growing quickly.

In general, you only need to repot your boxwood every two or three years — less if you’re growing them indoors in small containers.

Are Boxwood Bonsai Poisonous?

The answer is both yes, and no. Boxwood bonsai are not poisonous in the sense that they will cause a fatal reaction, but they are poisonous in that they contain chemicals that can be harmful to humans and animals.

Boxwood bonsai are toxic due to the presence of a substance called buxin, which is found throughout all varieties of boxwood. Buxin is toxic to both animals and humans, but it causes very different reactions depending on which species it affects.

Humans are relatively unaffected by ingesting small amounts of boxwood bonsai. The main effect experienced by humans is mild skin irritation, fueled by a chemical reaction between the buxin and the acids present in human skin.

However, contact with large quantities of buxin can lead to more severe reactions in humans. This occurs when the skin is exposed to large quantities of boxwood sap for an extended period of time or when ingested in large quantities.

Animals, however, exhibit much more severe reactions to boxwood bonsai as a result of buxin poisoning. These symptoms include drooling, diarrhea, vomiting, seizures, convulsions, and even death following ingestion or exposure to large quantities of boxwood bonsai.

So as a pet owner, you should make sure the bonsai are out of the reach of your pets.

Conclusion:

Boxwood Bonsai, also known as Buxus, are a very popular choice for bonsai. They grow well indoors and outdoors in part shade or full sun.

They can be shaped easily and tolerate pruning quite well. Boxwood bonsai are very versatile in that they can be kept small with regular trimming or allowed to grow larger by not trimming them much.