By Gary Wade
University of Georgia
Its popularity is partly because it's an excellent alternative to Leyland cypress, which has serious disease problems in the Southeast. It's being widely used to replace Leyland cypress hedges and screens across the Southeast.
Green Giant arborvitae is a fast-growing evergreen tree. Its rich green summer foliage darkens only a little during the winter. Mature trees have persistent, oblong cones a half-inch long that emerge green and turn brown.
Hardy throughout Georgia and the Southeast, Green Giant tolerates almost any soil condition and withstands adverse weather such as ice storms and wind. It has shown excellent pest resistance, too. Almost nothing bothers it. Even the deer don't browse it.
Think bigAs the name implies, Green Giant is a large plant, growing 50 to 60 feet tall and 20 to 30 feet wide. It's better suited for parks and large yards than for small lots with one-story homes. Once it's established, it can grow more than 3 feet per year in good growing conditions. That's another reason for its popularity.
If your landscape is too small for a mass planting of this large-growing plant, consider planting just one in the front of the home as a living Christmas tree. It develops a nice pyramidal shape naturally and requires little pruning. The soft-textured, dense foliage makes it easy to hang Christmas lights, too.
It was introduced by the U.S. National Arboretum in 1967. By the end of the century, it had captured lots of attention with its blemish-free foliage and exclamation-point form.
The original plant came from Denmark as a hybrid cross between Western red cedar (Thuja plicata) and Japanese arborvitae (Thuja standishii).
Green Giant is a public-domain tree, so anyone can propagate it, which is easily done with cuttings. That's another reason so many nurseries are beginning to offer it.
For best results, plant Green Giant arborvitae in full sun and a wide range of well-drained soils. It doesn't like wet, poorly drained soils.
Space the trees 15 feet apart in the row for best screening and wind resistance. Fertilize them in late winter and midsummer with granular fertilizer such as 16-4-8.
(Gary Wade is a Cooperative Extension horticulturist with the University of Georgia College of Agricultural and Environmental Sciences.)