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 color change begins which results in a mellow orange-ish 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.
This cultivar originating as a seedling selected by Jakub Jablonski of Poland from seed that came from Thuja occidentalis ‘Smaragd.’ Jantar is translated into amber in the polish language and is an accurate description of the plant’s winter color. It was introduced to the nursery trade by Breederplants, inc., Gouda, The Netherlands. Iseli Nursery, Boring Oregon is responsible for the U.S. introduction. This plant is patented (PP22296). ‘Jantar’ was one of three plants selected in 2016 for the ACS Collectors Conifer of the Year program.