Introduction
A North American native tree, Carolina silverbell grows into a 20- to 40-foot-tall tree with a 15- to 30-foot-spread into a pyramidal silhouette. The 2- to 4-inch-long leaves turn yellow in fall and are among the first to drop in autumn. The tree prefers sandy loam and begins blooming when only 10 to 12 feet tall. The pink, bell-shaped, showy blossoms are borne in 2- to 5-inch-long clusters. Flowering occurs along last year’s branches in mid-May 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 as they hang down from last year's branches. Carolina silverbell may transplant poorly in the fall.
General Information
Scientific name: Halesia carolina
Pronunciation: hal-EE-zhee-uh kair-oh-LYE-nuh
Common name(s): 'Rosea' Carolina silverbell
Family: Styracaceae
USDA hardiness zones: 5A through 8B (Figure 2)
Origin: native to North America
Invasive potential: native cultivar
Uses: specimen; street without sidewalk; deck or patio; tree lawn 3–4 feet wide; tree lawn 4-6 feet wide; tree lawn > 6 ft wide; container or planter
Description
Height: 20 to 40 feet
Spread: 15 to 30 feet
Crown uniformity: irregular
Crown shape: round, upright/erect, vase
Crown density: moderate
Growth rate: moderate
Texture: fine
Foliage
Leaf arrangement: alternate (Figure 3)
Leaf type: simple
Leaf margin: serrulate
Leaf shape: oblong, 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; showy; typically one trunk; thorns
Pruning requirement: little required
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: low
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. 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. They would make a perfect small-sized tree for planting near a deck or patio.
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. The tree grows best if roots are not confined to a small area and are allowed to explore a large soil area. Water during a drought and avoid compacted soil.
Propagation is by seeds sown as soon as ripe or stratified, and by layering, root cuttings, and greenwood cuttings. Small trees and seedlings transplant easily.
Pests and Diseases
No pests or diseases are of major concern.