Thuja koraiensis
Common Name: Korean arborvitae
Type: Needled evergreen
Family: Cupressaceae
Native Range: Central China, Korea
Zone: 5 to 8
Height: 15.00 to 30.00 feet
Spread: 10.00 to 15.00 feet
Bloom Time: Non-flowering
Bloom Description: Non-flowering
Sun: Full sun to part shade
Water: Medium
Maintenance: Low
Leaf: Evergreen
Other: Winter Interest

Culture

Grow in average, medium moisture, well-drained soils in full sun to part shade. Prefers moist, neutral to alkaline, well-drained loams. Intolerant of dry conditions. Best in full sun, but generally appreciates some light afternoon shade in hot summer climates such as the St. Louis area. Avoid full shade where foliage density will substantially decrease.

Noteworthy Characteristics

Thuja koraiensis, commonly called Korean arborvitae, is a small evergreen tree or large shrub that is native to valleys, slopes and mountain ridges in Korea and northeastern China. In its native environment, trees are often conical and slender in habit, but plants found on mountain ridges often appear as sprawling shrubs. In shrub form, it will grow to 15' tall, but as a tree will sometime rise to as much as 30' tall. Plants display attractive scale-like leaves in flattened sprays. Leaves are mat-green above with contrasting white stomatal bands underneath. Female cones (to 5/16" long) mature to reddish brown. Remaining populations of this tree in the wild in South Korea and China are protected. Populations in North Korea are reportedly unprotected.

Genus name is the Greek name for a kind of juniper (Juniperus.)

Specific epithet means of Korea.

Problems

No serious insect or disease problems.

Garden Uses

Interesting and uncommon small ornamental evergreen for the landscape. This tree is rare in commerce and may be difficult to locate.