Thuja occidentalis 'Jantar' is a narrow upright selection of arborvitae with invigorating, cheerful yellow foliage, with pointier tips at the terminals, especially at the top of the plant. Compared to other yellow selections of arborvitae, it has many more lateral branches which result in a much denser look. As cold weather approaches, a colour change begins which results in a mellow orange-yellow for winter. After 10 years in the landscape, one can expect a mature specimen to stand about 6 feet (2 m) tall and 18 inches (50 cm) wide, suggesting an annual growth rate of slightly less than 1 foot (30 cm) a year in most locations.