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American Holly

Ilex opaca (EYE-leks oh-PAH-kah)

Family: Aquifoliaceae Native Canopy (>40 ft)

American holly is a woody, broadleaf evergreen tree in the holly family (Aquifoliaceae) that has generated numerous cultivars. In nature, it is found growing as an understory tree or shrub in moist, deciduous forests in the central and southeastern United States.. The specific epithet, opaca, means dull, dark, or opaque in reference to the dullness of the leaf surface. American holly grows in moist, neutral to acidic soils in full sun to partial shade. It is intolerant of limestone soils. It will tolerate a range of soil textures, is moderately salt tolerant, and is highly deer resistant. It will tolerate occasionally wet or dry soil, but not flooding. For optimum growth, avoid poorly drained soils. Protect it from cold winter winds and winter sun. In hot summer climates, give it afternoon shade. Being situated in too much shade will cause the plant foliage to lose density. To have the bright red or orange berries that the holly is known for, both male and female plants must be present. Only female trees produce fruits and they must have a nearby male pollinizer. The American holly tree grows slowly, ultimately reaching from 40 to 60 feet tall and 10 to 20 feet wide in an open conical to pyramidal shape with limbs all the way to the ground. The evergreen leaves and fruits on female plants are fragrant and make for beautiful color and interest in a winter garden. Branches from this species are often used in the creation of Christmas wreaths. It is ideal for privacy screens, barriers, and hedges. It is not recommended for small yards, but can be a beautiful specimen plant when given ample space to grow. The fruit of the tree is a wildlife food source so, when space permits, consider including it in a butterfly, pollinator, native, or children’s garden. It serves as a host plant for the Henry's elfin ( Callophrys henrici ) butterfly. 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. Insects, Diseases, and Other Plant Problems: The leaves are typically yellow in alkaline soils. Twospotted spider mites, ash whitefly, soft scale insects, and leaf scorch. The Clemson Cooperative Extension Home and Garden Information Center has a factsheet on common diseases and insect pests. VIDEO: Part of the Native Plant Picks series from the North Carolina Sea Grant led Coastal Landscapes Initiative . Additional video Ilex opaca created by Andy Pulte for “Landscape Plant Identification, Taxonomy and Morphology” a plant identification course offered by the Department of Plant Sciences, University of Tennessee. More information on Ilex .

Source: NC State Extension Gardener Plant Toolbox ↗ Reconciled to full toolbox: matched by slug to slug 'ilex-opaca'. Identity (id/common/scientific name) preserved from the original 87-plant Hunnicutt set; attribute data refreshed from the 77-attribute toolbox scrape.

How it fits the guild

Guild layer 1 - Canopy (>40 ft) Optimal soil pH Acid (<6.0); Neutral (6.0-8.0)
See companions & conflicts ↓

Companions & Conflicts

Curated pairwise relationships between this plant and others in the library — who feeds whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.

No curated interactions recorded for this species yet.

Also noted by NC State

Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.

Often confused with Ilex x attenuata Ilex x attenuata Foster Hybrid Group Osmanthus x fortunei

Full plant profile

Growing Conditions
Plant type
Native Plant; Perennial; Poisonous; Tree
Life cycle
Woody
USDA zones
5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b
Light
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); Neutral (6.0-8.0)
Soil drainage
Good Drainage | Moist | Occasionally Dry | Occasionally Wet
Available space
3 feet-6 feet
NC region
Coastal; Mountains; Piedmont
Mature size
Height: 40 ft. 0 in. - 60 ft. 0 in. | Width: 10 ft. 0 in. - 20 ft. 0 in.
Growth rate
Slow
Maintenance
Low
Canopy layer
1 - Canopy (>40 ft)
Form & Appearance
Habit / form
Conical; Open; Pyramidal
Texture
Medium
Foliage
Broadleaf Evergreen
Leaf color
Green
Leaf type
Simple
Leaf arrangement
Alternate
Leaf shape
Elliptical; Oblong
Leaf margin
Entire
Leaf feel
Prickly
Leaf value
Showy
Leaf size
1-3 inches long, 1-3 inches wide
Hairs present
No
Leaf detail
Its thick, leathery, alternate, simple, deep green leaves (2 to 4 inches long) have spiny marginal teeth. Leaves are alternate, simple, oblong to elliptic, coriaceous, and have an apical spine.
Fall color
Brown/Copper; Gold/Yellow
Flower color
Gold/Yellow; Green; White
Flower value
Fragrant; Showy
Flower form
Cyme; Insignificant
Flower size
1-3 inches
Flower detail
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.
Bloom time
Spring; Summer
Fruit color
Orange; Red/Burgundy
Fruit type
Berry
Fruit value
Fragrant; Showy
Fruit size
< 1 inch long, < 1 inch wide
Fruit detail
Bright red or orange berry-like drupes appear on female plants after proper pollination. Persist on tree from September through February. Both sexes must be present to produce fruit (the plants are dioecious).
Bark color
Light Brown; Light Gray; Red/Burgundy; White
Bark detail
Light gray-white and smooth bark, may be splotched with red or tan lichens or warty.
Stem color
Gray/Silver
Stem detail
Stems are a greenish-gray color.
Wildlife & Ecology
Native status
Native
Origin
Central & Eastern U.S.A
Distribution
PA and MA south through FL, west to TX up through Midwest states
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.
Attracts
Bees; Butterflies; Pollinators; Small Mammals; Songbirds; Specialized Bees
Host plant for
Henry's Elfin (Callophrys henrici) larvae which appear from February to May and have one flight
Play value
Wildlife Food Source
Food & Medicine
Harvest time
Fall; Winter
Fruit type
Berry
Landscape Use
Landscape location
Coastal
Landscape theme
Butterfly Garden; Children's Garden; Native Garden; Pollinator Garden; Rain Garden
Design feature
Barrier; Hedge; Screen/Privacy; Specimen
Garden tags
#salt tolerant #specialized bees #evergreen #children's garden #foundation planting #honey bees #nectar plant #winter interest #fire high flammability #poisonous #Braham Arboretum #pollinator plant #larval host plant #fantz #native tree #NC native #food source herbage #food source nectar #food source pollen #Coastal FAC #food source fall #bird friendly #butterfly friendly #FACU Piedmont Mountains #winter cover #problem for cats #problem for dogs #problem for horses #Audubon #nectar plant early summer #nectar plant late spring #henry’s elfin butterfly #nectar plant mid-spring #food source soft mast fruit #bee friendly #showy fruits #playground plant #landscape plant sleuths course #food source winter #Christmas decorations #understory tree #understory shrub #highly beneficial coastal plants #slow growing #salt spray tolerant #red fruits #year-round interest #partial shade tolerant #storm damage resistant #wind tolerant #fragrant leaves #hedge #butterfly caterpillar host #wildlife friendly #cpp #rain garden #HS111 #HS303 #alkaline soils intolerant #illustration #hortcontest
Problems & Resistance
Insect problems
Soft Scale Identification and Management on Ornamental Plants; Leafminers of Hollies; Holly Berry Gall Midge; Pests of Holly; Managing the Twolined Spittlebug in the Home Landscape
Problems
Poisonous to Humans; Problem for Cats; Problem for Dogs; Problem for Horses
Resistant to
Deer; Salt; Storm damage; Wind
Particularly resistant to
Moderately salt tolerant, highly deer resistant.
Fire risk
high flammability
Poison severity
Low
Poison parts
Fruits
Poison symptoms
Nausea, vomiting (not in horses), diarrhea, depression.
Toxic principle
Illicin, possibly saponic glycosides, and triterpenoids.
Contact dermatitis
No
Toxicity summary
Low severity poison; parts: Fruits

Planted at Hunnicutt

Nobody’s planted this one yet.