Arborvitae or white cedars (Thuja occidentalis) are widely planted evergreens in home landscapes, windbreaks, and cemeteries in Iowa. Thuja occidentalis is a dense, pyramidal tree that can grow 30 to 40 feet tall. Its scale-like foliage is borne on flattened, fern-like sprays. The foliage emits an attractive, tansy-like fragrance when bruised or pruned. Arborvitae is Latin for "tree of life."
Arborvitae perform best in moist, well-drained, fertile soils. They can successfully be grown in full sun to partial shade. In heavy shade, arborvitae become loose and open.
Arborvitae have few insect or disease pests. However, they are not trouble-free. Arborvitae are susceptible to winter burn. Wind and sun can dry out the foliage during the winter months. The desiccated foliage turns brown in late winter/early spring. Arborvitae can also be severely damaged by browsing deer in winter.
Arborvitae foliage commonly varies from medium to dark green. However, several yellow or gold-leaved varieties are also available. In form, arborvitae cultivars vary from narrow to broadly pyramidal to globe-shaped. Cultivars vary in size from dwarf, 1- to 2- foot-tall shrubs to 30-foot-tall trees.
Upright, pyramidal varieties are commonly used as screens or hedges (formal or informal). They are also used as specimen plants at the corners of homes. The globe-shaped cultivars are often used as foundation plants or as accents in landscape beds. Dwarf varieties can be used in rock gardens.
A list of widely planted Thuja occidentalis cultivars, along with their growth characteristics, is provided below.
|'Brandon'||dark green||narrow pyramidal||12-15 ft./5-6 ft.|
|'Danica'||emerald green||globe||1-2 ft./1-2 ft.|
|'Degroot's Spire'||dark green||narrow pyramidal||6-10 ft./2-3ft.|
|'Emerald' ('Smaragd')||medium green||narrow pyramidal||12-15 ft./3-4 ft.|
|'Globosa'||medium green||globe||4-5 ft./4-5 ft.|
|'Golden Globe'||golden yellow||globe||3-4 ft./3-4 ft.|
|'Hetz Midget'||dark green||globe||3-4 ft./3-4 ft.|
|'Hetz Wintergreen'||dark green||narrow pyramidal||15-20 ft./5-7 ft.|
|'Holmstrup'||dark green||narrow pyramidal||6-8 ft./2-3 ft.|
|'Little Gem'||dark green||broad globe||2-3 ft./3- 4 ft.|
|'Little Giant'||medium green||globe||4-6 ft/4-6 ft.|
|'Lutea' ('George Peabody')||golden yellow||narrow pyramidal||25-30 ft./8-10 ft.|
|'Nigra'||dark green||narrow pyramidal||20-25 ft./7-8 ft.|
|'Pyramidalis'||medium green||narrow pyramidal||20-25 ft./5-8 ft.|
|'Rheingold'||gold||broad conical||4-6 ft./3-5 ft.|
|'Sunkist'||yellow-gold||pyramidal||10-12 ft./4-6 ft.|
|'Techny' ('Mission')||dark green||broad pyramidal||10-15 ft./10-12 ft.|
|'Wareana'||dark green||pyramidal||8-10 ft./4-6 ft.|
|'Woodwardii'||medium green||globe||4-6 ft./4-6 ft.|
This article originally appeared in the 6/25/2004 issue.