Thuja occidentalis 'Smaragd'

RHS Plant Profile
white cedar 'Smaragd'

Save a plant

Where do you want to save Thuja occidentalis 'Smaragd'?

Plants I own
Wishlist
Go to My Plants
white cedar 'Smaragd' RHS 2003
white cedar 'Smaragd' visionspictures.com

Synonyms

Thuja occidentalis 'Emeraude'
Thuja occidentalis Emerald

Award of Garden Merit
Conifers Shrubs
Thank you - your purchase supports our charity work Buy this from RHS Plants Shop
Buy online from £8.99Buy this from Plant Nurseries
18 Suppliers

A slow-growing, evergreen conifer with a conical habit and sprays of bright green, needle-like foliage. Makes an effective screen or shelter-belt or can be used as a stand-alone speciment

Position

Full sun

Soil Types

Chalk, Clay, Loam, Sand

Max Height

1.5-2.5 metres

Max Spread

1.5-2.5 metres

Size

Time to Maturity
10–20 years
Max Spread
1.5-2.5 metres
Max Height
1.5-2.5 metres

Growing Conditions

Chalk Clay Loam Sand
Moisture
Moist but well–drained
pH
Acid or Alkaline or Neutral

Position

Full sun
Aspect
East–facing or South–facing or West–facing
Exposure
Exposed or Sheltered
Hardiness

Hardiness Ratings

All ratings refer to the UK growing conditions unless otherwise stated. Minimum temperature ranges (in degrees C) are shown in brackets

  • H1A: under glass all year (>15C)
  • H1B: can be grown outside in the summer (10 - 15)
  • H1C: can be grown outside in the summer (5 - 10)
  • H2: tolerant of low temperatures, but not surviving being frozen (1 to 5)
  • H3: hardy in coastal and relatively mild parts of the UK (-5 to 1)
  • H4: hardy through most of the UK (-10 to -5)
  • H5: hardy in most places throughout the UK even in severe winters (-15 to -10)
  • H6: hardy in all of UK and northern Europe (-20 to -15)
  • H7: hardy in the severest European continental climates (< -20)
H7

Colour & Scent

Season Stem Flower Foliage Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family
Cupressaceae
Native to GB/Ireland
No
Foliage
Evergreen
Habit
Bushy
Potentially harmful
Harmful if eatenskin allergen. Wear gloves and other protective equipment when handling
Genus
Thuja are fast-growing evergreen trees of narrowly conical habit, with flat sprays of tiny, aromatic, scale-like leaves and small knobbly cones
Name Status
Accepted

How to Grow

Cultivation

Grow in moist but well-drained soil. Protect from drying winds especially when young

Propagation

Propagate by semi-hardwood cuttings

Suggested planting locations and garden types

  • Cottage and informal garden
  • Architectural
  • City and courtyard gardens
  • Patio and container plants
  • Rock garden
  • Low Maintenance
  • Flower borders and beds
  • Hedging and screens

Pruning

No pruning required

Pests

May be susceptible to scale insects and conifer aphid

Diseases

May be susceptible to honey fungus and other fungal diseases, particularly thuja blight and Coryneum canker (see conifers: brown patches)