Ilex crenata

Japanese holly is an evergreen shrub or small tree in the holly family (Aquifoliaceae). This holly is a native of Japan and East Asia and can be found in thickets, woods, and wet places in lowlands and mountains all across Japan. The shrub is dense, multi-stemmed, rigid, and compact with a rounded habit. It may slowly grow 5 to 10 feet tall and 5 to 8 feet wide. Many cultivars of this plant are even more compact and only grow 3 to 4 feet tall. The genus name, Ilex, comes from the Latin, Quercus ilex, for holm oak, and refers to the similarity of the leaves. The specific epithet, crenata, refers to the crenate margins or shallow rounded teeth on the edges of the leaves.

Plant in full sun to partial shade and in acidic well-drained soil. It tolerates drought, shade, air pollution, poor and clay soils, and is easy to transplant. However, it may not thrive in areas with high heat and humidity such as the southern United States. It is also best to plant this shrub in protected areas to prevent damage from winter's cold winds.

Japanese holly is dioecious, meaning that a separate male and female plant must be present for the female to be pollinated and produce fruit. If the female plant produces fruits, they are small, black, round drupes that ripen in the fall. There are many cultivars available and the parent species is rarely seen. 

Use Japanese holly as a border, foundation planting, hedge, in small groups, or in mass plantings. The shrub can be severely pruned to manage its size so it works well in small spaces and as topiary.

Quick ID Hints:

• Dense, multi-stemmed, rigid, and compact shrub or small tree with a rounded habit

• Small, alternate, glossy deep green leaves with crenate to serrulate margins

• Undersides of the leaves as translucent glands or black dots

• Clusters of small 4-petaled white flowers with greenish centers that bloom in the spring

• Small, black, round drupes that ripen in the fall

Insects, Diseases, and Other Plant Problems: Japanese holly has no serious insect pests or diseases. Spider mites and nematodes are occasional pests.  Aphids, scales, holly leaf miners, and holly leaf blight may also be seen. Alkaline soils will cause the leaves to yellow.

The Clemson Cooperative Extension Home and Garden Information Center has a factsheet on common diseases and insect pests.

VIDEO created by Ryan Contreras for “Landscape Plant Materials I:  Deciduous Hardwoods and Conifers or Landscape Plant Materials II:  Spring Flowering Trees and Shrubs” a plant identification course offered by the Department of Horticulture at Oregon State University