Styrax japonicus [STY-raks, juh-PON-ih-kuhs] is a deciduous flowering tree species of the Styracaceae family.
Native to Japan, Korea, and China, the plant features upward-facing ovate leaves and dark green-brown, olive-like fruits appearing after the flowering season and persisting till late autumn.
Since the green foliage faces upward, the flowers are easily visible even from a distance.
You may also hear it called by its common name, including:
- Japanese Snowbell Emerald Pagoda and Carillon are popular cultivars
Styrax Japonicus Care
Size & Growth
How fast do Japanese snowbell trees grow?
The Japanese Snowbell is slow to establish, growing only 12″ – 24″ inches a year. This small tree has a relatively compact habit that can take a very long time to get mature. It usually grows in a vase-shaped when young.
The snowbell tree typically grows up to 15’–25’ feet in height and sometimes has the same width. It is green and provides no real fall color.
What does a Japanese snowbell tree look like?
Japanese snowbell trees have a rounded shape and grow to be around 15’–25’ feet tall. They have glossy, dark green leaves with horizontal branching and produce small, white, flat-topped bell-shaped flowers in the spring.
It forms an upright, pyramidal shape with a horizontal branching canopy as it matures. Moreover, this plant is typically grown as a shrub or bushy tree.
How long does a Japanese snowball live?
Japanese snowball trees can live around 50 years.
What is the color of the leaves of Japanese snowbell trees in the fall?
The leaves of Japanese snowbell trees turn beautiful yellow to red color in the fall.
Flowering and Fragrance
As the name suggests, the plant produces white flowers with bell-shaped pendulous racemes hanging from the branches with showy yellow stamens.
The bell-shaped flowers are wonderfully fragrant, attracting bees and other pollinators when produced in abundant quantities in summer.
May-June is the peak bloom time with drooping clusters of beautiful white, waxy flowers.
Flowers give way to greenish-brown, ovoid (egg-shaped) drupes, often persisting into late autumn.
Light & Temperature
Styrax japonicus is a hardy plant. Although it prefers full sun exposure or dappled partial shade, it can tolerate temperatures as low as 5° degrees Fahrenheit (-15° C).
However, the young growth rate can get damaged by frosts.
Where does the Japanese snowball tree grow the best?
Japanese snowbell trees grow best in regions with a temperate climate, with mild summers and cool winters. They prefer moist, well-drained soil and partial shade, although they can tolerate full sun in cooler regions.
The planting location USDA Zone – hardiness zone 5 – 8, must be protected from cold and dry winds.
Watering and Feeding
Japanese snowbell plants need moderately moist soil when planted. However, their water requirements reduce once they are established.
Mature Styrax japonica trees need occasional watering only in summer.
As for feeding, apply a general, balanced, granular fertilizer right after the semi-dormant pruning.
Soil & Transplanting
This deciduous tree plant type can grow in clay, sandy, and loamy soils.
However, it thrives in organically rich, well-drained, and moderately moist acid soil.
While it prefers acidic pH, the plant can grow in soils of neutral pH.
Grooming and Maintenance
In winter, prune styrax trees, as needed, to give the desired shape.
How do you maintain a Japanese snowbell?
On average, it doesn’t require a lot of maintenance. Maintaining a Japanese snowbell tree involves regular watering, fertilizing, and pruning.
The tree should be watered during dry periods and fertilized in the spring with a slow-release fertilizer.
How do you prune a Japanese snowbell?
Pruning the plant a couple of times is usually enough to keep it in shape.
It’s also best to prune your Japanese snowball annually in late winter or early spring to remove dead or damaged branches and improve air circulation.
How to Propagate Japanese Snowbell
Styrax japonicus is propagated by seeds and softwood cuttings.
The ripe seeds are available in abundant quantities in October.
However, the seeds need double dormancy to ensure the best germination rate.
This means that late spring is the best time to sow the seeds, so they can get the required warmth during the summer, followed by the cold in the winter season.
Some people also sow fresh seeds after they are picked in autumn.
With this method, the seeds will likely germinate only partially in the spring.
You are likely to wait for a year for full germination.
Styrax japonicas plants are also rooted through softwood cuttings.
The best time to take cuttings is in early summer.
For best results, treat the cuttings immediately with a hormone-rooting compound.
However, while rooting the softwood cuttings is a fairly quick and easy process, it is difficult to make them survive through winter and shoot in the next spring.
To avoid damage to the root system during winter, the cuttings need to be kept frost-free and dry.
Even when all the guidelines are followed, many people find it difficult to propagate styrax japonicas through softwood cuttings.
While propagation through seeds takes a long time, it is easier and more likely to succeed than propagation through softwood cuttings.
Japanese Styrax Pest or Diseases
No serious disease or pest problems are identified. However, stressed plants may get affected by the ambrosia beetle.
Aphids are attracted to new young shoots. If you catch them early, a spray blast of water from the garden hose can work.
Severe attacks from these pest insects need treating with special insecticides.
More on Getting Rid of Aphids
Japanese Snowbell Uses
Due to their beautiful flowers, Styrax japonicus plants are popularly used in landscaping, enhancing an area’s aesthetic appeal.
Their extraordinary bark has interlacing orange-brown fissures that also interest the landscape during the cold winter.
They are widely grown in park garden designs, woodland gardens, and cemeteries.
In Japan, the fragrant Japanese snowbell trees are commonly seen on roads and streets. They are also excellent plants near a patio, on a border, or lawn.
The seeds are sometimes used to extract oil.
Historically, the wood of the tree was widely used to make walking sticks, umbrella handles, implements, toys, and Japanese chess pieces.