Plant of the Week
Latin: Cryptomeria japonica
During the winter months, we gardeners long for a touch of green. In recent years, nurserymen have been becoming reacquainted with many conifers that provide winter color but are different than the too-common pines. One of these rediscoveries is Japanese cedar (Cryptomeria japonica), a forest giant from far-off Asia.
Cryptomeria is a tall, pyramidal evergreen conifer capable of reaching 40 feet in 30 years with a spread of 15 to 20 feet. In a moist location with deep, fertile soil, trees may eventually reach 60 feet or more in height. Cryptomeria belongs to the cypress family and is monotypic, with only this one species in the genus. In Japanese it is called suji (straight trunk), where it is their national tree. It is native to both Japan and much of southern China and is extensively planted around temples and shrines.
Young trees make fast growth, so the top of the tree is often more open than lower portions of the plant. With age, the lower limbs will be shed if the trees are planted in a dense grove. The bark is juniper-like in appearance, except it tends to be red-tinged. In Japan, Cryptomeria is a common timber species grown for its pinkish softwood lumber that is lightweight, strong and decay-resistant.
The lumber has redwood-like characteristics and is used for posts for traditional Japanese teahouses. In the mountains north of Tokyo, it is grown as a coppice plant with the main stems cut back occasionally to form long, skinny poles for use as rafters in the teahouses. It is also used for interior paneling.
The evergreen leaves are awl-shaped, as found in junipers, but to a quarter-inch long. They are spirally arranged around the young branches and persist for four to five years. The summer foliage color is a bright green that turns bronzy-green (or brownish during severe winters) in the winter. The round cones are produced at the ends of branches and are about an inch across.
Cryptomeria was first described from material collected in Japan in 1692 and China in 1701, but living specimens did not make their way to the West until the middle of the 19th century. Seeds arrived in Washington, D.C., about 1858. Because it is easily propagated by cuttings, as many as 200 named cultivars of this plant have been made.
'Yoshino', a more compact version of the species and said to retain better leaf color during the winter than the average seedling, is currently being grown by nurseries throughout the southeastern states and touted as better than all the rest. More compact versions, such as 'Black Dragon,'20 feet;, 'Compacta,' 40 feet; 'Elegans,' a form with juvenile foliage growing to 20-plus feet; 'Taisho Tama,' 20 feet; and many others are offered by specialists and are better used where space will be limited. 'Sekkan-sugi' has golden foliage in the spring that fades to green in summer.
Cryptomeria is considered easy to grow, but it lacks drought tolerance. It should be planted in deep, moderately moist sites where it is sheltered from drying winds. Plants are hardy from zones 5 through 8. It has good shade tolerance. Use it in a compact grove to create a stately effect as single specimens or, if some of the more dwarf clones are chosen, as a part of the foundation planting.
By: Gerald Klingaman, retired
Extension Horticulturist - Ornamentals
Extension News - March 26, 2010
The University of Arkansas Division of Agriculture does not maintain lists of retail outlets where these plants can be purchased. Please check your local nursery or other retail outlets to ask about the availability of these plants for your growing area.