Big-leafed Storax Styrax obassia

The fragrant snowbell is a large-leaved deciduous flowering tree. This beautiful tree grows to a height of 20 to 30 feet and has an upright and pyramidal habit when young and then becomes rounded with age. It gets its common name from the 6- to 8-inch-long racemes of fragrant and showy white flowers that appear in late spring to early summer. Blooming after the leaves emerge, the flowers' beauty can be hidden by the foliage.  After flowering, drupes are formed. They may be present into late autumn.  

This tree is native to Japan, Korea, and Manchuria. It was first introduced into cultivation in 1870. The genus name, Styrax, is Greek in origin and references resin-producing plants. The epithet, obassia, is a Japanese name.

Growing best in well-drained, acidic soil, it can be planted in the sand, clay, or loam-based locations.  It does not do well when soil is compacted.  In cooler planting zones, protection from winter winds is required. The leaves and flower buds can be damaged by frost. In the warmer zones, full sun is not recommended.  Locate in an area that receives some protection from the hot summer sun. It is moderately drought tolerant, once established.

The bark is smooth and gray and older specimens can experience exfoliation which reveals a showy inner layer.  This orange layer will often provide winter interest. Its leaves are bold, dark-green, ovate, pubescent on the undersides, and up to 8 inches long. The fragrant bell-shaped flowers have showy golden yellow stamens. The fruits appear in late summer as silvery-green round to oval drupes.

To control the shape of this tree, it is best to prune it in the winter.  To achieve a more shrub-like form, prune annually by cutting the top back in the late summer to about one-half of its height.  For a multi-stemmed habit is recommended to cut back the plant by one-half every 2 to 3 years.  A tree form can be accomplished by removing any upward-growing branches. This should be accomplished in the winter months. As the plant ages, it will tend to droop, requiring pruning for clearance underneath.

The beautiful fragrant snowball tree is one of the most underused trees in the landscape. Consider this tree as a small specimen in your home landscape or as a woodland understory tree.

Seasons of Interest:

Bark:  Winter     Bloom:  Spring       Foliage:  Spring, Summer and Fall      Fruits:  Fall and Summer

Quick ID Hints:  

• fragrant and flowering tree with a pyramidal to rounded habit, measuring 20 to 30 feet tall and 15 to 25 feet wide
• smooth gray bark and has orange-brown vertical fissures (older trees exfoliate)
• large, bold, dark green leaves with pubescence on the undersides
• fragrant, drooping bell-shaped white to creamy colored flowers with golden stamens in late spring to early summer
• fruits are 3/4-inch round to oval, silvery-green drupes that appear in clusters in late summer

Insects, Diseases, and Other Plant Problems:  No significant disease or pest issues.  The foliage and flower buds are susceptible to frost injury in late winter and early spring.

VIDEO created by Andy Pulte for “Landscape Plant Identification, Taxonomy and Morphology” a plant identification course offered by the Department of Plant Sciences, University of Tennessee.