Platycladus orientalis, commonly known as Oriental Arborvitae, Chinese Arborvitae, or Biota, is an evergreen conifer native to northeastern Asia, specifically China, Korea, and the Russian Far East. Cultivated for centuries due to its resilient nature and dense foliage, it is highly valued in modern landscaping for its adaptability and ability to be shaped. Beyond its ornamental use, Oriental Arborvitae holds cultural meaning and has been a component of traditional medicine for thousands of years.
Identifying Oriental Arborvitae
The identification of Platycladus orientalis begins with its unique scale-like foliage, arranged in distinctive, flattened, vertical sprays. The leaves are small, typically less than three millimeters long, triangular, and have a blunt point. Unlike related genera, the scales are not closely pressed to the stem tip.
The foliage is usually medium to yellowish-green during the growing season, often developing a bronze or brownish cast during winter months. When crushed, the leaves release a distinct aromatic odor. The tree is dense and conical or pyramidal when young, but older specimens tend to become more open or irregular in shape.
The cones start as small, fleshy, blue-green structures roughly 1.5 to 2.5 centimeters long. As they mature, they dry out, turning medium brown and developing a woody texture. They feature several irregular, horn-like projections or hooked scales at the end, giving the mature fruit a unique appearance. The bark on mature trees is reddish-brown and peels in long, thin strips.
Essential Growing Requirements
Platycladus orientalis thrives best in full sunlight, ideally receiving six or more hours of direct sun exposure daily. While it tolerates light shade, protection from intense afternoon sun in warmer climates helps prevent leaf scorch. Adequate air circulation is beneficial for maintaining health and dense growth.
The species is adaptable to various soil types, but the medium must be well-drained to prevent root problems. Loamy or sandy soils with a slightly acidic to neutral pH are preferred, as the plant will not tolerate boggy or saturated conditions. If planted in heavy clay, situating it on a slope helps ensure drainage.
Once established, Oriental Arborvitae tolerates drought, reducing the need for frequent supplemental watering. During establishment or periods of extreme heat, water deeply whenever the top inch or two of soil feels dry. Apply a balanced, slow-release fertilizer in the spring.
Pruning is the primary maintenance task for shaping or hedging. Light shaping can be performed throughout the growing season, but major structural pruning is best done in late winter or early spring before new growth begins. Avoid cutting deeply into the older, inner wood, as this compromises the plant’s ability to generate new foliage.
Popular Varieties and Aesthetic Uses
The species form is often used as a specimen tree or background screen, but a wide range of cultivars have been developed to suit specific landscape needs. These varieties offer variation in size, growth habit, and foliage color. Dwarf varieties are useful for smaller spaces and foundation plantings.
Popular dwarf cultivars include ‘Aurea Nana’, which maintains a dense, rounded form with bright yellow-green foliage, and ‘Compacta’, which grows into a dense, pyramidal shape ideal for formal applications. For winter color, the dwarf shrub ‘Morgan’ features yellowish foliage that shifts to an attractive orange-bronze.
Taller, upright cultivars also serve distinct aesthetic functions, such as ‘Conspicua’, a large conical plant with prominent yellow foliage. Fast-growing varieties are used to form wind screens or tall hedges, while smaller forms are perfect for rock gardens, low borders, or accent plantings.
Traditional Significance and Medicinal History
Platycladus orientalis is associated with concepts of long life and vitality in East Asia. In Traditional Chinese Medicine (TCM), the plant is known as Cebaiye, and its use has been documented for over two millennia. Practitioners used the plant to address a variety of ailments, classifying its effects as cooling and calming.
The leaves and seeds are the primary parts used in traditional remedies. The foliage was commonly prescribed as a hemostatic agent to stop various forms of bleeding, including nosebleeds and internal hemorrhages. The leaves were also used to treat inflammatory conditions like coughs and fevers.
Essential oils extracted from the leaves are recognized for their antimicrobial and antioxidant properties. The seeds were traditionally valued for their sedative effects, often prepared to help alleviate symptoms of restlessness, headaches, and insomnia. Modern research suggests its flavonoids may support scalp circulation, supporting the historical use of the plant for promoting hair growth.