Mark A. Miller
Family
Aquifoliaceae
Botanical Name
Ilex opaca
Plant Common Name
American Holly
General Description
American holly is an elegant evergreen tree that's ideal for home landscapes. Its dense branching, pyramidal habit and smooth gray bark are only a few of the appealing attributes of this broadleaf evergreen. Wild specimens grow in forests across the eastern half of the United States, from Maine to Texas, and are particularly common from the Appalachian Piedmont to the Atlantic coastal plain.
The spiny, oval leaves of American holly are stiff and dull, dark green. Cultivars tend to have slightly glossy foliage. Sharp, yellowish spines that are painful to the touch arm the undulating leaf edges. Each leaf will persist on a tree for up to three years before falling. Small, white or greenish flowers appear in late spring or early summer on the current year's growth. The trees are dioecious, which means each specimen has either male or female flowers, never both. Only female trees yield red or orange-red berries in the fall, but male trees are needed for pollination and fruit-set. The colorful berries last well into the winter. Birds will eat the fruit over the course of the season.
Landscape specimens perform best if provided plenty of sunshine and fertile soil with an acid to neutral pH. Established trees are tolerant of drought and will withstand the wind, saltspray and sandy soil near the ocean. Drying summer or winter winds, however, cause leaf desiccation. American holly also grows best in moist, average to well-drained soils rich in organic matter. Fast-draining sandy soils may be wet without causing these trees to succumb to root rot and fungal diseases.
Over 1,000 American holly cultivars have been selected and bred. These vary in size, habit, berry and leaf color as well as climatic and soil tolerances. A few of the more widely known cultivars include the glossy-leaved 'Dan Fenton', yellow-fruited ‘Canary’ and popular male pollinator, 'Jersey Knight.'
Characteristics
-
AHS Heat Zone
9 - 1
-
USDA Hardiness Zone
5 - 9
-
Sunset Zone
2a, 2b, 3a, 3b, 4, 5, 6, 7, 8, 9, 14, 15, 16, 17, 19, 20, 21, 22, 23
-
Plant Type
Broadleaf Evergreen
-
Sun Exposure
Full Sun, Partial Sun
-
Height
25'-50' / 7.6m - 15.2m (40)
-
Width
15'-40' / 4.6m - 12.2m (25)
-
Bloom Time
Late Spring
-
Native To
United States, Northeastern United States, Mid-Atlantic United States, Southeastern United States, Central United States, South-Central United States, Texas
Growing Conditions
-
Soil pH
Acidic, Neutral
-
Soil Drainage
Average
-
Soil type
Clay, Loam, Sand
-
Tolerances
Salt
-
Growth Rate
Slow
-
Water Requirements
Drought Tolerant, Average Water
-
Habit
Pyramidal
-
Seasonal Interest
Spring, Summer, Fall, Winter
Ornamental Features
-
Flower Interest
Insignificant
-
Flower Color
White
-
Fruit Color
Red
-
Foliage Color (Spring)
Green, Light Green
-
Foliage Color (Summer)
Green, Dark Green
-
Foliage Color (Fall)
Dark Green
-
Foliage Color (Winter)
Dark Green
-
Bark Color
Gray
-
Fragrant Flowers
Yes
-
Fragrant Fruit
No
-
Fragrant Foliage
No
-
Bark or Stem Fragrant
No
-
Flower Petal Number
Single
-
Repeat Bloomer
No
-
Showy Fruit
Yes
-
Edible Fruit
No
-
Showy Foliage
Yes
-
Foliage Texture
Medium
-
Foliage Sheen
Matte
-
Evergreen
Yes
-
Showy Bark
No
