Winterberry Ilex opaca
Other Common Name(s):
Other plants called Winterberry:
Previously known as:
- Ilex × attenuata
- Phonetic Spelling
- EE-leks oh-PAY-kah
- This plant has low severity poison characteristics.
- See below
- Description
-
American Holly is an evergreen tree that may grow 40 to 60 feet tall. The tree has alternate leaves with spiny toothed and sometimes smooth margins. The bark is gray-white in color and may be splotched or warty. Small, dull green-white, solitary flowers mature in late spring. Female specimens produce a bright red or orange fruit which matures in the fall and persists into the winter.
The American Holly is easily grown in average, consistently moist, acidic, well-drained soils in full sun to part shade. The leaves are typically yellow in alkaline soils and have a dusty, dirty look to them. It will tolerate a broad range of soil conditions and is pollution tolerant, but will not tolerate flooding or soils saturated with moisture. For optimum growth avoid poorly drained soils. Its best growth in the wild usually occurs in rich bottomlands and swamp margins. It will not do well in locations not protected from cold winter winds and winter sun. Part afternoon shade is best in hot summer climates. Being situated in too much shade will cause the plant foliage to lose density. Uses for this large tree that may have limbs all the way to the ground include privacy screens and specimen plantings. It doesn’t make a good plant for small yards, but can be a beautiful plant when given space to grow.
Fire Risk: This plant has a high flammability rating and should not be planted within the defensible space of your home. Select plants with a low flammability rating for the sites nearest your home.
Quick ID Hints:
- Dull, dark green leaves are both entire and spiny.
- Spines are evenly spaced and are long and sharp.
- Leaves usually have a dull, dirty look.
- See this plant in the following landscapes:
- Woodland Backyard Garden Walk
- Cultivars / Varieties:
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- 'Crooneburg'
more upright, narrower - 'Fallow'
- 'Greenleaf'
- 'Howard'
has few spines - 'Kleimi'
- 'William Hawkins'
- 'Crooneburg'
- 'Crooneburg', 'Fallow' , 'Greenleaf' , 'Howard', 'Kleimi', 'William Hawkins'
- Tags:












- Cultivars / Varieties:
-
- 'Crooneburg'
more upright, narrower - 'Fallow'
- 'Greenleaf'
- 'Howard'
has few spines - 'Kleimi'
- 'William Hawkins'
- 'Crooneburg'
- 'Crooneburg', 'Fallow' , 'Greenleaf' , 'Howard', 'Kleimi', 'William Hawkins'
- Tags:
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Attributes:
- Genus:
- Ilex
- Species:
- opaca
- Family:
- Aquifoliaceae
- Life Cycle:
- Woody
- Country Or Region Of Origin:
- Central & Eastern U.S.A
- Distribution:
- PA and MA south through FL, west to TX up through Midwest states
- Fire Risk Rating:
- high flammability
- Wildlife Value:
- This plant provides nectar for pollinators. It is a larval host plant for Henry's Elfin (Callophrys henrici) larvae which appear from February to May and have one flight. Adult Henry's Elfin butterflies feed on flower nectar. Its fruits are eaten by songbirds, wild turkeys, quail, white-tailed deer, squirrels and other small mammals. Honeybees are attracted to its tiny white flowers. This tree provides cover during the winter.
- Play Value:
- Wildlife Food Source
- Particularly Resistant To (Insects/Diseases/Other Problems):
- Moderately salt tolerant, highly deer resistant.
- Dimensions:
- Height: 40 ft. 0 in. - 60 ft. 0 in.
- Width: 10 ft. 0 in. - 20 ft. 0 in.
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Whole Plant Traits:
- Plant Type:
- Native Plant
- Poisonous
- Tree
- Woody Plant Leaf Characteristics:
- Broadleaf Evergreen
- Habit/Form:
- Open
- Pyramidal
- Growth Rate:
- Slow
- Maintenance:
- Low
- Texture:
- Medium
- Appendage:
- Spines
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Cultural Conditions:
- Light:
- Deep shade (Less than 2 hours to no direct sunlight)
- Full sun (6 or more hours of direct sunlight a day)
- Partial Shade (Direct sunlight only part of the day, 2-6 hours)
- Soil Texture:
- Clay
- Loam (Silt)
- Shallow Rocky
- Soil pH:
- Acid (<6.0)
- Soil Drainage:
- Good Drainage
- Moist
- Occasionally Dry
- Occasionally Wet
- Available Space To Plant:
- 3 feet-6 feet
- NC Region:
- Coastal
- Mountains
- Piedmont
- USDA Plant Hardiness Zone:
- 5a, 5b, 6b, 6a, 7a, 7b, 8a, 8b, 9b, 9a
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Fruit:
- Fruit Color:
- Orange
- Red/Burgundy
- Fruit Value To Gardener:
- Fragrant
- Showy
- Display/Harvest Time:
- Fall
- Winter
- Fruit Type:
- Berry
- Fruit Length:
- < 1 inch
- Fruit Width:
- < 1 inch
- Fruit Description:
- Bright red or orange berry-like drupe. Persist on tree from September through February. Both sexes must be present to produce fruit (dioecious).
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Flowers:
- Flower Color:
- Gold/Yellow
- Green
- White
- Flower Inflorescence:
- Cyme
- Insignificant
- Flower Value To Gardener:
- Fragrant
- Showy
- Flower Bloom Time:
- Spring
- Summer
- Flower Size:
- 1-3 inches
- Flower Description:
- The American Holly is dioecious (male and female flowers are on separate trees). It has greenish-white flowers bloom April-June (male flowers in 3-12 flowered clusters and female flowers solitary or in 2's or 3's). Infloreescence is staminate a cyme, and pistillate single.
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Leaves:
- Woody Plant Leaf Characteristics:
- Broadleaf Evergreen
- Leaf Color:
- Green
- Leaf Feel:
- Prickly
- Leaf Value To Gardener:
- Showy
- Deciduous Leaf Fall Color:
- Brown/Copper
- Gold/Yellow
- Leaf Type:
- Simple
- Leaf Arrangement:
- Alternate
- Leaf Shape:
- Elliptical
- Oblong
- Leaf Margin:
- Entire
- Hairs Present:
- No
- Leaf Length:
- 1-3 inches
- Leaf Width:
- 1-3 inches
- Leaf Description:
- Its thick, leathery, alternate, simple, deep green leaves (2-4" long) have spiny marginal teeth. Leaves are alternate, simple, oblong to elliptic, coriaceous, and have an apical spine.
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Bark:
- Bark Color:
- Light Gray
- White
- Bark Description:
- Light gray-white and smooth bark, may be splotched or warty.
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Stem:
- Stem Color:
- Gray/Silver
- Stem Is Aromatic:
- No
- Stem Description:
- Stems are a greenish-gray color.
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Landscape:
- Landscape Theme:
- Butterfly Garden
- Children's Garden
- Pollinator Garden
- Design Feature:
- Barrier
- Hedge
- Screen/Privacy
- Specimen
- Attracts:
- Bees
- Butterflies
- Pollinators
- Small Mammals
- Songbirds
- Specialized Bees
- Resistance To Challenges:
- Deer
- Salt
- Wind
- Problems:
- Frequent Disease Problems
- Poisonous to Humans
- Problem for Cats
- Problem for Dogs
- Problem for Horses