American arborvitae

Thuja occidentalis ‘Nigra’¬†or arborvitae ‘Nigra’. This member of the Cupressaceae is native to North America from Manitoba eastward throughout the Great Lakes region to the northeastern United States. Sporadic, isolated populations can be found as far south as Tennessee and North Carolina.

In nature, plants are found in wet forests and coniferous swamps, where individuals can grow up to 60 ft. tall with a trunk diameter of up to 1.5 ft. Thuja occidentalis can be long-lived if growing in an area protected from wildfire and browsing by deer. The oldest known T. occidentalis grows on an isolated cliff in southern Ontario and is at least 1,650 years old.

A primary feature of arborvitae is its evergreen fan-like branches covered in scale-like green leaves. In the fall and winter, slender yellow-green immature cones can develop on plants. These cones enlarge and open in the late fall and early winter, becoming brown to red-brown as they mature. The high degree of variation in foliage and growth habit in arborvitae has led to selection of over 300 cultivars for use as ornamentals in the landscape. You may not realize that Lurie Garden’s shoulder hedge is comprised of four selections of arborvitae–giving the hedge a delicate variation in color and texture!

Botanical Name Thuja occidentalis ‘Nigra’
Common Name arborvitae ‘Nigra’
Family Cupressaceae
USDA Zone 3 thru 7
Light Requirement Full Sun to Part Shade
Season(s) of interest All Seasons
Height and Spread
20-30ft x 5-10ft (6-9m x 1.5-3m)
Flower Color Non-flowering
Attracts Wildlife
Pollinators, Provides Food for Birds, Hosts Butterflies/Moths
Additional Information
Cultivated Form of a Plant Native to the Chicago Region
Location in Lurie Garden Shoulder Hedge