Oriental Arborvitae (Thuja orientalis)

Oriental Arborvitae

Thuja orientalis

Its flat sprays hold year-round green, a quiet evergreen anchor. Coniferous shrub or small tree; common name: Chinese Arborvitae.

Full sun
1–2/week
Beginner
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Plant Needs

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Sunlight Full sun to partial shade; full sun promotes dense, compact growth, while partial shade prevents leaf scorch in hot climates
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Watering Water deeply when the top 5 cm of soil dries out; drought-tolerant once established, avoid overwatering to prevent root rot
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Temperature Hardy to -20°C; withstands hot summer temperatures but prefers cool to temperate growing conditions
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Characteristics

  • Leaf: Scale-like, flattened aromatic sprays, dark green to bronze in winter
  • Cones: Small oval brown mature cones with 6–8 woody scales
  • Stem: Densely branching woody stems forming compact, layered growth
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Care Guide

Watering

Keep soil evenly moist during active growth periods

Fertilization

Apply a balanced slow-release fertilizer once at the start of growth. Avoid over-fertilizing to prevent excessive, weak growth

Eggshell powder topdress:Crush dried eggshells to a fine powder, sprinkle a 1 cm layer on the soil surface, and water gently to release calcium into the root zone
Pruning
  • Prune in late spring to maintain desired shape; shear hedges lightly 2–3 times per growing season
  • Remove dead, diseased, or crossing branches to improve airflow and reduce pest risk
  • Thin dense inner growth to allow light penetration and prevent fungal issues
  • Avoid heavy pruning of old wood, as it has limited regrowth capacity
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Toxicity

Warning: this plant may be toxic.

Pets & Humans

Pets: ASPCA: Toxic due to thujone content; may cause vomiting, diarrhea, lethargy, and muscle tremors

Humans: Ingestion may cause mild gastrointestinal upset; prolonged skin contact may trigger mild irritation

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Garden Uses & Culture

Culture: Symbolizes longevity and resilience in traditional Chinese garden design; historically used in limited traditional medicinal preparations (not recommended for modern consumption due to toxicity)

Usage: Ornamental hedge, topiary specimen, windbreak, and landscape accent plant