Introduction

'Rosea' mountain silverbell grows into a 40-foot tree in its natural habitat but is about 20 to 30 feet tall in gardens and landscapes, with an upright-spreading crown. The tree prefers sandy loam and begins blooming when only 10 to 12 feet tall. The flowers are larger than those of Halesia carolina. The pale pink, bell-shaped blossoms are borne in clusters of up to five. Flowering occurs along last year’s branches in mid-spring on the previous season's wood. Because the flowers point downward, they are partially hidden by the foliage and best viewed from below. Other ornamental features are the yellow fall color and the bark, which peels off in large, flat scales. The pale-yellow fruits are quite attractive. Mountain silverbell may transplant poorly in the fall.

General Information

Scientific name: Halesia monticola

Pronunciation: hal-EE-zhee-uh mawn-tih-KOLE-uh

Common name(s): 'Rosea' mountain silverbell

Family: Styracaceae

USDA hardiness zones: 5A through 8B (Figure 2)

Origin: native to North America

Invasive potential: not assessed/incomplete assessment

Uses: specimen; street without sidewalk; tree lawn 4–6 feet wide; tree lawn > 6 ft wide; highway median; container or planter

Description

Height: 40 to 60 feet

Spread: 20 to 30 feet

Crown uniformity: irregular

Crown shape: vase, oval, pyramidal

Crown density: moderate

Growth rate: fast

Texture: medium

Foliage

Leaf arrangement: alternate (Figure 3)

Leaf type: simple

Leaf margin: serrate

Leaf shape: elliptic (oval), ovate

Leaf venation: pinnate

Leaf type and persistence: deciduous

Leaf blade length: 2 to 4 inches, 4 to 8 inches

Leaf color: green

Fall color: yellow

Fall characteristic: showy

Flower

Flower color: pink

Flower characteristics: very showy

Fruit

Fruit shape: oval

Fruit length: 1 to 3 inches

Fruit covering: dry or hard

Fruit color: yellow

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

Trunk and Branches

Trunk/bark/branches: branches droop; not showy; typically one trunk; thorns

Pruning requirement: needed for strong structure

Breakage: resistant

Current year twig color: brown

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; occasionally wet

Drought tolerance: moderate

Aerosol salt tolerance: none

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

This tree is interesting all year long, with attractive medium green foliage, pretty flowers, showy fruits, and exfoliating bark. It branches low to the ground, making a nice lawn or specimen tree and when pruned to one central leader can be used as a street tree in residential areas in less than full-day sun. The bark shows off nicely with foliage removed from the lower branches, and multi-stemmed specimens come-to-life when lit from below at nighttime.

An understory tree best suited for a partially shaded or shaded location, silverbell prefers moist, fertile soil with an accumulation of leaf litter and/or mulch. Water during a drought and avoid compacted soil.

Pests and Diseases

No pests or diseases of serious concern, occasionally leaf spot.