Platycladus orientalis 'Westmont'

Common Name: Chinese arborvitae 
Type: Needled evergreen
Family: Cupressaceae
Zone: 6 to 9
Height: 2.00 to 4.00 feet
Spread: 2.00 to 4.00 feet
Bloom Time: Non-flowering
Bloom Description: Non-flowering
Sun: Full sun to part shade
Water: Medium
Maintenance: Medium
Leaf: Colorful, Evergreen
Other: Winter Interest

Culture

Grow in fertile, medium moisture, well-drained soils in full sun. Tolerates some light afternoon shade. Appreciates good air circulation. Water plants regularly in hot and dry weather. In St. Louis, site in locations sheltered from strong winds. Plants may not be reliably winter hardy throughout the northern parts of USDA Zone 5.

Noteworthy Characteristics

Platycladus orientalis, commonly called oriental thuja or oriental arborvitae, typically grows as a dense, conical to columnar tree to 18-25’ tall. Also grows as a large shrub. Plants tend to open up with age. Scale-like yellowish-green leaves in flattened sprays in youth, becoming darker green with age. Foliage may bronze up in winter. Oval cones (to 3/4” long). Reddish-brown bark. Compact shrubby cultivars are much more common in cultivation than the species. Synonymous with Thuja orientalis and Biota orientalis.

Genus name comes from the Greek platys meaning broad and klados meaning a branch for the branchlets being two-ranked in a vertical plane.

Specific epithet means of the Orient.

'Westmont' is a compact, slow-growing, upright-globular form (2" per year) that will typically reach only 26" tall by 18" wide over the first 10 years. Scale-like foliage is dark green tipped with bright yellow. Foliage may bronze up in winter. Platycladus orientalis ‘Westmont’ is synonymous with and formerly known as Thuja orientalis ‘Westmont’. U.S. Plant Patent PP2,685 was issued for this cultivar in 1965.

Problems

Healthy, well-maintained plants sited in proper growing environments usually have few major problems. Watch for bagworms and spider mites. Scales, aphids, caterpillars, borers and mealybugs may appear. Branches may be broken from snow weight in winter.

Uses

Small hedge, foundation, border, accent or small garden. Container.