Western Red Cedar
thuja plicata
Also known as: ["Red Cedar","Western Arborvitae","Canoe Cedar"]
Overview
A large, long-lived evergreen tree native to the Pacific Northwest, valued for its aromatic wood and ornamental foliage.
Benefits & Perks
["disease resistant","cold hardy","wildlife attractant (bees, butterflies, birds)","shade tolerant"]
Botanical Classification
| Phylum: | Pinophyta |
| Class: | Pinopsida |
| Order: | Pinales |
| Family: | Cupressaceae |
| Genus: | Thuja |
| Botanical Name: | Thuja plicata |
Plant Characteristics
Basic Information
- Category: Trees
- Suitable Location: outdoor garden, sheltered from strong winds
- Suitable For:
- Is Weed: No
- Allergenicity: low
Environmental Needs
- Climate: {"temperatureRange":"0–35°C, tolerates occasional dips to -15°C"}
- Hardiness: {"zones":"5–7"}
- Misting: rarely required, only if indoor air is very dry
- Drainage: Moderate to fast-draining.
- Soil Type: Well-draining, loamy soil with added organic matter.
Maintenance Level
- Maintenance Level: moderate
- Toughness Level: high
- Pruning Frequency: Annually in late winter or early spring before new growth begins.
- Pruning Intensity: Moderate to heavy, depending on desired shape and size.
Care Details
Ideal Sunlight Coverage:
Full sun to partial shade (4–6 hours of direct sunlight daily). Tolerates shade but may become sparse.
Sunlight Tolerance Tips:
Acclimate gradually to intense sunlight to avoid scorching. Protect from harsh afternoon sun in hot climates. Outdoor placement is ideal, but ensure filtered light indoors.
Care Requirements
Care Difficulty
easymoderate
Sunlight
full sun to partial shade
Monitor for leaf scorch, provide dappled shade in summer, rotate plant for even growth.
Watering
every 7–10 days, more frequently in hot, dry conditions
Water thoroughly until runoff, allow soil to dry slightly between waterings, and avoid overwatering to prevent root rot.
Soil
moist, well-drained, acidic to slightly alkaline loam
pH: Acidic to slightly acidic (pH 5.5–6.5).
Ensure good drainage, maintain slightly acidic pH, enrich with organic matter.
Temperature
Hardy in USDA zones 5–7, tolerates temperatures between -25°C to 30°C. Prefers cool roots and moderate temperatures.
Protect from frost, avoid extreme heat, maintain consistent temperatures.
Fertilizing
every 2–3 months during active growth (spring and summer)
Use a balanced NPK fertilizer, water before and after application, avoid over-fertilizing.
Propagation
Methods
Stem cuttings taken in late spring or early summer.
Step-by-Step Propagation Guide
- Take 4–6 inch cuttings, remove lower leaves, apply rooting hormone, plant in medium, maintain humidity, and wait for roots.
Best Time: Late spring to early summer when new growth is firm but not woody.
Environment
High humidity (70–90%), indirect light, and consistent warmth (18–24°C).
Medium
Peat-based mix with perlite or sand for good drainage.
Hormone
Rooting hormone is recommended to improve success rates.
Timeline
Roots may develop in 4–8 weeks; establishment takes 6–12 months.
Tools Needed
Pruning shears, rooting hormone, propagation tray, humidity dome, misting spray bottle.
Quick Tips
Use healthy parent material, maintain consistent moisture, avoid direct sunlight.
Pruning & Repotting
Pruning Guide
Method
Selective thinning, heading back, and shaping cuts to maintain form.
Pruning Plan
Prune to maintain shape, remove dead/diseased wood, and encourage denser growth.
Tools
Pruning shears, loppers, saw (for larger branches), sterilizing solution.
Checklist
Sterilize tools, prune dead/diseased wood first, make clean cuts, avoid over-pruning.
Repotting Guide
Best Season
Early spring before active growth begins.
Pot Size
Increase pot size by 2–5 cm (1–2 inches) in diameter.
Method
Remove plant gently, trim roots if necessary, use fresh soil mix, ensure good drainage, water lightly after repotting.
Suggestions
Repot every 2–3 years or when roots fill the container. Young plants may need repotting annually.
Checklist
Check root bound status, prepare new pot, trim roots if needed, use fresh soil, water lightly, place in shade temporarily.
Advanced Care Tips
Watering Mastery
Watering Checklist
Check soil moisture, water deeply, ensure drainage, avoid wetting foliage, adjust seasonally.
How to Apply Water Properly
Water at the base of the plant, ensuring moisture reaches the root zone. Water early in the morning to minimize evaporation and allow foliage to dry before nightfall.
Watering Schedule Tips
Water deeply once a week during spring and summer, reducing frequency to every 2–3 weeks in fall and winter. Adjust based on rainfall and soil moisture.
Soil Improvement
Add compost, perlite, or sand to improve drainage and aeration. Adjust pH with peat moss or sulfur if needed.
Temperature Stress Management
Signs of Temperature Issues
Chlorosis, needle drop, stunted growth, or browning of foliage.
Cold Stress
Leaves may turn brown or drop, and growth can slow or stop in prolonged cold.
Solution: Mulch heavily around the base, protect from harsh winds, and avoid planting in frost pockets.
Hot Stress
Needles may brown, wilt, or drop, and growth may cease during extreme heat.
Solution: Provide shade during peak heat, increase watering, and ensure good air circulation.
Fertilizing Guide
Fertilizing Checklist
Check soil nutrients, use correct dilution, apply during active growth, avoid winter feeding.
Fertilizing Method
Use a balanced, slow-release fertilizer in early spring. Apply a second light feeding in midsummer if needed. Avoid fertilizing in fall or winter.
Common Problems & Solutions
Toxicity Warning
Cats
Slightly ToxicCats may experience mild gastrointestinal upset if they ingest Thuja plicata seeds or berries. The toxicity is generally low but can cause discomfort.
⚠️ Symptoms:
🌿 Toxic Parts:
⚡ Toxic If:
if eaten
Dogs
Slightly ToxicIn dogs, ingestion of Thuja plicata seeds and berries can lead to mild gastrointestinal upset. The plant is not highly toxic but can cause discomfort.
⚠️ Symptoms:
🌿 Toxic Parts:
⚡ Toxic If:
if eaten
Humans
Slightly ToxicThuja plicata, commonly known as Western Red Cedar, contains compounds that can cause mild gastrointestinal distress when ingested. The toxic effects are generally not severe but can be uncomfortable.
⚠️ Symptoms:
🌿 Toxic Parts:
⚡ Toxic If:
if eaten
Frequently Asked Questions
Q: Is Thuja plicata suitable for small gardens?
A: No, it is a large tree and requires ample space to grow.
Q: Does Western Red Cedar attract wildlife?
A: Yes, it provides habitat and food for birds and other wildlife.
Q: Is the wood of Thuja plicata aromatic?
A: Yes, its wood has a distinct, pleasant aroma.
Quick Reference
| Family: | Cupressaceae |
| Care: | easy |
| Light: | full sun to partial shade |
| Water: | every 7–10 days, more freque |
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