1 / 4
Broadleaf Deciduous Trees
Styrax obassia
fragrant snowbell
StyracaceaeJapan, Korea, northern China
At a Glance
TypeTree
HabitUpright
FoliageDeciduous
Height20-30 feet (6-9 m)
Width15-25 feet (4.6-7.6 m)
Maturity15 years
Growing Zones
USDA Hardiness Zones
5 - 8Zone 5
Zone 6
Zone 7
Zone 8
These zones indicate the coldest temperatures this plant can typically survive.
Frost Tolerancehardy
Key Features
Attracts Pollinators
Deer Resistant
Fragrant (moderate)
Maintenancevery low
Overview
Styrax obassia is a deciduous tree reaching 20-30 feet (6-9 m) tall with a spread of 15-25 feet (4.6-7.6 m), developing a rounded to broadly pyramidal crown with a more upright habit than S. japonicus. The primary distinguishing feature is the foliage: leaves are alternate, simple, broadly orbicular to obovate, very large at 4-8 inches (10-20 cm) across, nearly round, with a velvety soft, pubescent underside. The bold, large-leaved texture is a dramatic contrast to the fine-textured S. japonicus and is unusual among small ornamental trees. Flowers are white, bell-shaped, fragrant, 0.75-1 inch (2-2.5 cm) across, borne in pendant terminal racemes 4-8 inches (10-20 cm) long in June — longer and more prominent racemes than S. japonicus. Fragrance is stronger than S. japonicus, sweet and pleasant. Bark is smooth, gray, attractive. Fall color is yellow, not a strong feature. Growth rate is moderate at 12-18 inches (30-46 cm) per year. Less commonly planted than S. japonicus but equally worthy as an ornamental. The large leaves create a bold, tropical-looking texture unusual in temperate trees.
Native Range
Native to Japan, Korea, and northern China, occurring in moist montane forests. The name 'obassia' derives from a Japanese common name for the tree.Suggested Uses
Planted as a specimen or accent tree where the bold foliage texture and fragrant flowers can be appreciated, spaced 15-20 feet (4.6-6 m) from other trees. The large, round leaves provide a bold, almost tropical textural contrast in mixed plantings. Site near seating areas to enjoy the fragrance. Effective at woodland edges and in courtyard settings. Combines well with fine-textured plants (ferns, Japanese maples) for contrast. Less commonly available than S. japonicus but well worth seeking out.How to Identify
Appearance
Size & Dimensions
Height20' - 30'
Width/Spread15' - 25'
Reaches mature size in approximately 15 years
Colors
Flower Colors
white
Foliage Colors
green
Fall Foliage Colors
yellow
Bloom Information
Bloom Period
~3 weeksJ
F
M
A
M
J
J
A
S
O
N
D
Summer
Detailed Descriptions
Flower Description
WhiteFoliage Description
Dark green, very large and boldGrowing Conditions
Sun Requirements
Full Sun
Partial Shade
Requires 4-8 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Soil Requirements
pH Range5.0 - 6.5(Acidic)
357912
Soil Types
loampeat
Drainage
well drained
Water & Climate
Water Needs
Medium
Frost Tolerance
hardy
Time to Maturity
5-8 years
Care & Maintenance
Care Guide
Water regularly; consistent moisture is important. Mulch 3-4 inches (8-10 cm) with organic matter. Plant in part shade to full sun; afternoon shade prevents leaf scorch on the large leaves. Requires acidic, moist, well-drained soil rich in organic matter. Protect from hot, drying winds, which can damage the large, soft leaves. Essentially pest- and disease-free in the Pacific Northwest. The large leaves can be damaged by hail or strong winds; a sheltered location is ideal.Pruning
Minimal pruning needed. Establish a central leader in youth. Remove crossing, dead, and damaged branches in late winter. Maintain natural form. The rounded crown develops naturally with age. Low branches may be removed to create a tree-form canopy, but retain some lower branches for flower viewing at close range.Pruning Schedule
J
F
M
A
M
J
J
A
S
O
N
D
winter