Winterberry Ilex opaca

American holly is a woody, broadleaf evergreen tree in the Aquifoliaceae (holly) family that has generated numerous cultivars. In nature, it is found growing as an understory tree or shrub in moist, deciduous forests in central and southeastern United States. The genus name Ilex is in reference to the similarity of the evergreen leaves to Quercus ilex. 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 will tolerate a range of soil textures, is moderately salt tolerant, and 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. In order to produce the bright red or orange berries that the holly is known for, both male and female plants must be present.  

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.

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. 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.  

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.

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.