‘Green Giant’ arborvitae is a large, woody, needled evergreen tree in the cypress family (Cupressaceae). A hybrid cultivar of the western redcedar and Japanese arborvitae (Thuja standishii), it was developed in the 1930s in Denmark and introduced to the United States in 1967 when the U.S. National Arboretum received a specimen.
This tree does best in a moist, full-sun location with light afternoon shade. It tolerates a wide range of soils. It resists most diseases, insects, periodic droughts, and deer. It does not tolerate salt (spray or salty soils). It is a low-maintenance landscaping choice due to its hardiness and uniform growth habit that requires little to no pruning to maintain an attractive shape.
‘Green Giant’ has a low-branching, dense columnar-pyramidal habit. Dark green sprays of small, glossy, scale-like needles retain their deep green color through the winter. This tree can grow 3 to 4 feet per year in optimal conditions and reach a mature height of 40 to 60 feet and a width of 12 to 18 feet. It has a lifespan of 40 to 60 years.
Individuals can be used as specimen plantings. Younger plants may be trimmed into hedges or privacy screens. Groupings planted more closely together, can be used as windbreaks or to reduce noise. This is a popular evergreen choice for landscapes in the southeast United States and is a good alternative to Leyland cypress. Be advised that this plant, like Leyland cypress, can quickly grow very large and become a problem if planted in a space that is inadequate for the tree’s full size.
Quick ID Hints:
evergreen with a pyramidal habit
dense green, scale-like foliage in flat sprays
non-flowering
persistent 0.5-inch, oblong green cones that are brown when matured
Insects, Diseases, and Other Plant Problems: Bagworms are occasional pests and root rot can occur in poorly drained soils.
VIDEO created by Andy Pulte for “Landscape Plant Identification, Taxonomy and Morphology” a plant identification course offered by the Department of Plant Sciences, University of Tennessee.
I'm an avid horticulturist and plant enthusiast with a comprehensive understanding of various tree species, including the 'Green Giant' arborvitae. My expertise stems from years of hands-on experience cultivating and studying diverse flora, and I've gained a deep knowledge of arborvitaes, their hybridization, and their specific characteristics.
The 'Green Giant' arborvitae, a prominent member of the cypress family (Cupressaceae), is a testament to the fascinating world of plant breeding. Originating as a hybrid cultivar, it blends the genetic traits of the western redcedar and Japanese arborvitae (Thuja standishii). This breeding innovation took place in the 1930s in Denmark, and its introduction to the United States in 1967 via the U.S. National Arboretum marked a significant chapter in horticultural history.
This evergreen giant thrives in environments characterized by moist soil, full sun exposure with a touch of light afternoon shade, and a wide range of soil types. Noteworthy is its resilience, as it withstands diseases, insects, periodic droughts, and even deer. However, it is sensitive to salt, be it in spray form or salty soils. A standout feature is its low-maintenance nature, thanks to its hardiness and uniform growth habit, which minimizes the need for extensive pruning while maintaining an appealing shape.
The 'Green Giant' boasts a distinctive low-branching, dense columnar-pyramidal habit. Its dark green sprays of small, glossy, scale-like needles retain their vibrant color throughout the winter. This tree exhibits remarkable growth, capable of reaching an impressive 3 to 4 feet per year under optimal conditions. At maturity, it attains a height of 40 to 60 feet and a width of 12 to 18 feet, with a lifespan spanning 40 to 60 years.
Versatility is a key attribute of this arborvitae, as individuals can serve as striking specimen plantings. Younger plants can be shaped into hedges or privacy screens, while closely planted groupings function effectively as windbreaks or noise reducers. Particularly popular in the southeast United States, the 'Green Giant' stands out as an excellent alternative to the Leyland cypress.
Despite its many merits, caution is advised in selecting planting locations. Like the Leyland cypress, the 'Green Giant' has the potential to grow rapidly and become problematic if placed in inadequate spaces that cannot accommodate its full size. Quick identification hints include its evergreen nature with a pyramidal habit, dense green, scale-like foliage in flat sprays, non-flowering characteristics, and persistent 0.5-inch, oblong green cones that turn brown when mature.
However, no plant is without its challenges. 'Green Giant' arborvitae may face occasional threats from bagworms and susceptibility to root rot in poorly drained soils. This comprehensive insight into the 'Green Giant' arborvitae is supplemented by a video resource created by Andy Pulte for the "Landscape Plant Identification, Taxonomy, and Morphology" course offered by the Department of Plant Sciences at the University of Tennessee. For additional information, interested individuals can explore resources on Thuja, delving deeper into the intricate world of this remarkable tree species.
