Thuja Green Giant Arborvitae

Thuja ‘Green Giant’ is a fast-growing evergreen hybrid with an upright, pyramidal form and dense green foliage. Its parentage is Thuja standishii × T. plicata; the established cultivar name identifies the hybrid selection, so its full hybrid identity is retained. ## Form and landscape use This conifer is grown for tall screening and windbreaks, and its uniform outline seldom needs pruning. Monrovia describes growth to roughly 25–30 feet tall and 8–10 feet wide at ten years, with height increasing to 50–60 feet over time; allow room for its eventual scale. The foliage remains green through the year, making the plant useful where a substantial evergreen screen is wanted. ## Siting Monrovia lists USDA Zones 5–8 and full sun. It advises watering when the top two inches of soil are dry, avoiding poorly drained wet sites, and watering deeply during the first few growing seasons. Once established, plants need less frequent watering and tolerate drought. Its broad soil adaptability is useful, but drainage remains important. ## Maintenance The naturally uniform form generally requires little pruning, though it responds to shearing when a screen needs shaping. Apply general-purpose fertilizer before new spring growth and maintain deep watering while the root system establishes. [Monrovia Green Giant profile](https://www.monrovia.com/green-giant-western-arborvitae.html) · [Kew Plants of the World Online: Thuja plicata](https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:60443333-2)