Photo: National Park Service, Public domain · Wikimedia Commons

Northern White Cedar

Thuja occidentalis

Also called arborvitae, eastern arborvitae, American arborvitae, eastern white cedar.

The wild arborvitae, a narrow, fragrant evergreen of northern cedar swamps and limestone cliffs that makes a dense screen.

EvergreenHedge or screenTolerates wet soilWildlife valueWinter interest

Type: Medium tree
Mature height: 40–60 ft
USDA zones: 2–7
Growth rate: Slow
Sun: Full, Part
Soil moisture: Average, Wet
Grows wild in: Rocky ground, stream banks, swamps and wet flats
Native range: 21 states, north and west to Minnesota and south to North Carolina
List all 21
Connecticut, Illinois, Indiana, Kentucky, Maine, Maryland, Massachusetts, Michigan, Minnesota, New Hampshire, New Jersey, New York, North Carolina, Ohio, Pennsylvania, Rhode Island, Tennessee, Vermont, Virginia, West Virginia and Wisconsin
Also recorded in 2 other states, outside its native range. See what is native in your state

Hardiness zones Find your zone by ZIP code

Northern white cedar is the parent species of the many garden arborvitae, and it was probably the first North American tree taken to Europe, about 1566. One wild tree on the cliffs of the Niagara Escarpment in Ontario was dated at 1,032 years. Its foliage is a favorite winter food of deer, and heavy browsing by deer and hares has kept young trees from replacing old ones across wide areas. Indiana, Massachusetts and New Jersey list it as endangered. Connecticut, Kentucky and Maryland list it as threatened. Plant a row as a windbreak or a hedge along a property line.

Size, growth and what to expect

Northern white cedar grows slowly, about a foot a year in our growth estimator. On a good site it can reach 40 feet in 50 years, but only 15 feet on a poor one. It matures at 40 to 60 feet with a narrow crown 10 to 15 feet wide, often on two or more trunks. Trees can live more than 400 years.

Pollen is shed from late April to early June, and the small cones ripen in August and September. The upright cones are a third to half an inch long and open like little roses to drop their winged seed. White-tailed deer winter in its stands, and warblers and kinglets nest in the densest ones.

It grows wild from Nova Scotia and Quebec west to Manitoba and Minnesota, and south to northern Illinois, central Michigan and central New York. Isolated stands grow farther south along the Appalachians, to Virginia and Tennessee. Unlike Atlantic white cedar, a tree of acid bogs, it favors soils rich in lime.

How to grow Northern White Cedar

Northern white cedar grows in full sun or part shade, and it thins out in full shade. It prefers a moist, well-drained loam that is neutral to alkaline, and it takes clay and wet sites. It stands periodic high water but dies in ground that stays flooded. Avoid dry, windy spots, where the foliage burns in winter. Plant it 15 feet from a wall, and set trees 10 feet apart for a screen. Keep it more than 50 feet from overhead wires.

Saplings ship bare-root or potted. Plant in early spring or fall, in a hole wider than the roots and no deeper. Set the root flare at the soil line, put the native soil back in, and keep the mulch clear of the trunk. Sow seed outdoors in fall, an eighth of an inch deep. For a spring sowing, keep it damp in the refrigerator for 30 to 60 days first. Seedlings come up in late spring.

Water weekly through the first two summers and in dry spells after that. Deer browse it hard in winter and can kill trees shorter than about 7 feet, so fence or cage young trees. Hares and voles also cut and girdle seedlings. It takes shearing well as a hedge.

Each tree carries both male and female cones and the wind carries the pollen. It sets seed readily with its own pollen, so one tree bears alone. It can bear cones at 6 years, and good crops come every 3 to 5 years. Arborvitae leafminers damage the leaf tips, and bagworms and spider mites turn up on planted trees. Heavy snow and ice can break its stems. It has few serious diseases.

Heights and zones are typical ranges for the species in cultivation; local conditions and seed source shift them.

Sources (13)