Introduction

Japanese Snowbell is a small deciduous tree that slowly grows from 20 to 30 feet in height and has rounded canopy with a horizontal branching pattern. With lower branches removed, it forms a more vase-shaped patio-sized shade tree. The smooth, attractive bark has orange-brown interlacing fissures adding winter interest to any landscape. The white, bell-shaped, drooping flower clusters of Japanese Snowbell are quite showy in May to June.

General Information

Scientific name: Styrax japonicus

Pronunciation: STY-racks juh-PAWN-ih-kuss

Common name(s): 'Emerald Pagoda' Japanese Snowbell

Family: Styracaceae

USDA hardiness zones: 5A through 8A (Fig. 2)

Origin: not native to North America

Invasive potential: little invasive potential

Uses: trained as a standard; parking lot island < 100 sq ft; parking lot island 100-200 sq ft; parking lot island > 200 sq ft; tree lawn 3-4 feet wide; tree lawn 4-6 feet wide; tree lawn > 6 ft wide; specimen; street without sidewalk; deck or patio; container or planter; sidewalk cutout (tree pit); highway median

Availability: not native to North America

Description

Height: 20 to 30 feet

Spread: 15 to 25 feet

Crown uniformity: symmetrical

Crown shape: round, vase

Crown density: moderate

Growth rate: slow

Texture: medium

Foliage

Leaf arrangement: alternate (Fig. 3)

Leaf type: simple

Leaf margin: sinuate/undulate, entire, serrate

Leaf shape: oblong, elliptic (oval)

Leaf venation: pinnate, brachidodrome

Leaf type and persistence: deciduous

Leaf blade length: less than 2 inches, 2 to 4 inches

Leaf color: green

Fall color: yellow, red

Fall characteristic: not showy

Flower

Flower color: pink

Flower characteristics: showy

Fruit

Fruit shape: oval, round

Fruit length: less than .5 inch, .5 to 1 inch

Fruit covering: fleshy

Fruit color: green

Fruit characteristics: does not attract wildlife; not showy; fruit/leaves not a litter problem

Trunk and Branches

Trunk/bark/branches: branches droop; showy; typically multi-trunked; thorns

Pruning requirement: little required

Breakage: resistant

Current year twig color: green

Current year twig thickness: thin

Wood specific gravity: unknown

Culture

Light requirement: full sun, partial sun or partial shade

Soil tolerances: clay; sand; loam; acidic; slightly alkaline; well-drained

Drought tolerance: moderate

Aerosol salt tolerance: moderate

Other

Roots: not a problem

Winter interest: yes

Outstanding tree: yes

Ozone sensitivity: unknown

Verticillium wilt susceptibility: unknown

Pest resistance: free of serious pests and diseases

Use and Management

Styrax species is an excellent small patio tree where the flowers and interesting bark can be viewed up close; however, the flowers attract tremendous numbers of bees and one should be cautious about approaching the plant at that time. Japanese Snowbell also makes a wonderful addition to the mixed shrubbery border. Due to its small stature and vase-shape, it can make a nice street tree where overhead space is limited. The fruit is somewhat showy and may cause a small litter problem for a short time in the fall. Fall leaf color is unreliable.

Snowbell prefers a peaty, acid soil that is moist but not waterlogged. In colder areas (USDA hardiness zone 5), locate this tree in an area protected from winter winds. Plants grow better with a couple hours of shade in USDA hardiness zones 7 and 8 but full sun is fine in the North.

Cultivars include: `Carillon' is hardy only to zone 6, grows about one-foot per year and has a weeping habit, can be staked to encourage weeping habit; `Crystal' - upright to fastigiate habit, black green foliage, crisp white flowers with purple pedicels (zone 5); `Issai' - cold hardy to zone 6, grows faster that species and roots easily; `Pink Chimes'- pink flowers, cold hardy to zone 6.

Propagate by softwood cuttings in summer. Seeds eventually germinate but exhibit a double dormancy.

Pests and Diseases

No pests or diseases of major concern. Ambrosia beetle can attack and lead to further decline of stressed plants.