Introduction

Carolina buckthorn develops an open crown of many slender branches and is usually seen at 12 to 15 feet in height although it is capable of reaching 40 feet in a partially shaded location. The bright green, deciduous leaves change to a gorgeous orange/yellow or red in autumn before dropping. The fairly inconspicuous, early summer flowers are greenish-white and followed by small, showy red fruits which ripen to black in the fall when their flesh becomes sweet and edible. Birds find the fruits irresistible. The thin, smooth bark is gray with dark markings. Carolina buckthorn is quite attractive in the landscape and is one of the first fruiting plants to show color.

General Information

Scientific name: Frangula caroliniana

Pronunciation: FRAYN-goo-luh kair-oh-lin-ee-AY-nuh

Common name(s): Carolina buckthorn

Family: Rhamnaceae

USDA hardiness zones: 5A through 9B (Figure 2)

Origin: native to North America

Invasive potential: native

Uses: hedge; trained as a standard; reclamation; highway median; deck or patio; specimen; container or planter

Description

Height: 12 to 15 feet

Spread: 10 to 15 feet

Crown uniformity: irregular

Crown shape: oval

Crown density: open

Growth rate: moderate

Texture: medium

Foliage

Leaf arrangement: alternate (Figure 3)

Leaf type: simple

Leaf margin: entire, serrulate

Leaf shape: oblong, elliptic (oval)

Leaf venation: pinnate

Leaf type and persistence: deciduous

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

Leaf color: green

Fall color: orange, red

Fall characteristic: showy

Flower

Flower color: yellow

Flower characteristics: not showy

Fruit

Fruit shape: round

Fruit length: less than 0.5 inch

Fruit covering: fleshy

Fruit color: black, red

Fruit characteristics: attracts birds; showy; fruit/leaves not a litter problem

Trunk and Branches

Trunk/bark/branches: branches droop; not showy; typically multi-trunked; 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, shade tolerant

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

Drought tolerance: high

Aerosol salt tolerance: unknown

Other

Roots: not a problem

Winter interest: no

Outstanding tree: no

Ozone sensitivity: unknown

Verticillium wilt susceptibility: unknown

Pest resistance: resistant to pests/diseases

Use and Management

Use this small tree or large shrub in a shrub border to attract birds and for a late summer accent. It can be planted in mass to form a thicket which should provide food and cover for a variety of wildlife. It might also be tried as a street tree where overhead space is restricted by power lines.

Carolina buckthorn should be grown in full sun on well-drained soil, acid or alkaline. It is moderately drought-tolerant.

Propagation is by seed.

Pests

No pests are of major concern.

Diseases

Susceptible to crown rust of oats. A leaf spot will occasionally infect the tree but is of no consequence.