Arborvitae care — light, water, toxicity and hardiness
Arborvitae (Thuja occidentalis) wants full sun and a drink about every 7 days once established. It is hardy in USDA zones 3 to 7. It is toxic to pets — worth keeping out of reach.
| scientific name | Thuja occidentalis |
|---|---|
| family | Cupressaceae |
| category | shrub |
| plant type | perennial |
| light | full sun |
| water cadence days | 7 |
| mature height cm | 400 |
| min zone | 3 |
| max zone | 7 |
| frost tolerant | true |
| toxic to pets | true |
| toxic to humans | false |
| edible | false |
How often should I water Arborvitae?
Water deeply the first two summers; deer candy.
Who eats it
Palatable to browsing animals such as deer: medium. Palatable to grazing animals: low. Palatable to people: no.
What it needs
Its shade tolerance is medium. Its moisture use is medium. Its drought tolerance is low. It wants at least about 35 inches of rain a year. Above roughly 55 inches of annual rain it struggles. It tolerates soil down to pH 5.2. It tolerates soil up to pH 7.0. Its fertility requirement is medium. Adapted to coarse, sandy soils: yes. Adapted to medium, loamy soils: yes. Adapted to fine, clay soils: yes. Its tolerance of waterlogging is medium. It needs at least 100 frost-free days. Its salt tolerance is medium. Its tolerance of chalky soil is high. Its fire tolerance is low. Fire resistant: no. It has been recorded down to -33°F. It suppresses neighbours chemically: no.
How it grows
It grows as a single stem form. Its growth rate is slow. Its lifespan is long. It puts on most of its growth in spring and summer. It spreads by seed at a moderate rate. It resprouts after damage: no. Coppices: no. Its tolerance of hedging is high. At maturity it reaches about 50.0 feet. By twenty years it is about 25 feet. Its roots go down at least 30 inches. Its shape is conical. It holds its leaves through winter: yes.
What it looks like
It blooms in mid spring. Conspicuous in flower: no. The foliage is green. The foliage texture is fine. In summer the canopy is dense in porosity. In winter it is dense in porosity. Fall colour: no. The fruit or seed is brown. Fruit begins in summer. Fruit finishes by fall. It fruits medium. The fruit persists on the plant: yes. The fruit is conspicuous: no.
Growing more of it
Propagated by seed: yes. Propagated by cuttings: yes. Propagated by container: yes. Propagated by bare root: yes. Propagated by bulb: no. Propagated by corm: no. Propagated by tubers: no. Cold stratification required: yes. Seedling vigour is medium. Commercial availability: routinely available.
Source: Drafted from US Cooperative Extension horticulture guidance; pending HUMAN-05 review (issue 280) · ASPCA Toxic and Non-Toxic Plant List · 2026-09-02