Common Name: Japanese holly
Type: Broadleaf evergreen
Family: Aquifoliaceae
Zone: 5 to 9
Height: 4.00 to 6.00 feet
Spread: 0.75 to 1.00 feet
Bloom Time: May
Bloom Description: White
Sun: Full sun to part shade
Water: Medium
Maintenance: Medium
Suggested Use: Hedge
Flower: Insignificant
Leaf: Colorful, Evergreen
Attracts: Birds
Other: Winter Interest
Tolerate: Clay Soil, Air Pollution
Culture
Easily grown in average, medium moisture well-drained soils in full sun to part shade. Tolerant of a wide variety of soils ranging from moist to dry and from sand to clay. Prefers light, moist, acidic soils with good drainage. Established plants have some tolerance for drought. Plants may struggle in climates with hot, humid summers. Plants are dioecious (male and female flowers on separate plants), so both male and female plants must be present in order for the female plant to be pollinated and produce fruit.
The yellow foliage of 'NCIC2' shows good resistance to sunburn and winter damage.
Noteworthy Characteristics
Ilex crenata, commonly known as Japanese holly or box-leaved holly, is a dense, multi-branched, evergreen shrub with a rounded form that typically matures to 5-10’ tall and as wide. It is native to forests, thickets and mountain slopes in Japan, Korea, China and eastern Russia (Sakhalin). It is noted for its ovate to elliptic, crenate to serrulate, glossy, spineless, evergreen, deep green leaves (to 1.25" long) which are attractive all year, 4 petaled, white, somewhat inconspicuous, flowers which bloom in 3-7 flowered cymes from late spring into early summer, and black rounded somewhat inconspicuous fruits (drupes to 0.25" diameter) which mature in fall on pollinated female plants.
Genus name comes from the Latin name Quercus ilex for holm oak in reference to the foliage similarities (holm oak and many of the shrubs in the genus Ilex have evergreen leaves).
Specific epithet is in obvious reference to the crenate margins of the leaves.
'NCIC2' is a narrow, columnar, female selection of Japanese holly that features yellow-green new growth that matures to dark green. This cultivar was selected from seed grown, third generation crosses of Ilex crenata 'Sky Pencil' and I. crenata 'Golden Gem'. Mature plants will reach up to 6' tall and 1' wide. Commonly sold at nurseries and garden centers under the name GLOW STICK. US plant patent number PP36325 applies to this cultivar.
Problems
Spider mites and root nematodes can be problematic.
Uses
Mass or group. Hedge. Borders. Incorporate into a foundation planting.