Platycladus orientalis, commonly called the Chinese arborvitae or Oriental thuja, is a hardy evergreen conifer that is easy to identify by its flattened, fan-shaped sprays of scale-like leaves. To grow it successfully, plant it in full sun with well-drained soil, and water it regularly during its first year to establish deep roots. This tree tolerates heat, drought, and a wide range of soil types once established, making it a reliable choice for hedges, screens, or a specimen plant in most US climates.
What Does Platycladus Orientalis Look Like?
This tree looks different from many other evergreens. Instead of needle-like foliage, it grows flattened, vertical sprays that look like fans or fern fronds. The scale-like leaves are small and overlapping, giving each branch a smooth, textured appearance.
The foliage color changes with the seasons. In summer, the leaves are a rich green or sometimes a blue-green. In winter, many varieties turn a bronze or copper color, especially in colder climates. This winter color change is normal and the green returns in spring.
Mature trees develop an upright, oval or conical shape. In cultivation, it usually reaches 15 to 25 feet tall, though some specimens grow taller in ideal conditions. The bark is reddish-brown and peels in thin strips, adding winter interest. Female trees produce small, blue-green cones that look like tiny berries before they mature to a woody brown.
How To Grow And Identify Platycladus Orientalis: Site Selection
Location matters more than almost anything else for this tree. Platycladus orientalis needs full sun. Six or more hours of direct sunlight per day is ideal. In too much shade, the foliage becomes sparse and the plant loses its dense, full appearance.
Soil drainage is the next critical factor. This tree does not tolerate wet feet. If the soil stays soggy after rain, the roots can rot. Sandy loam or any well-drained garden soil works well. It tolerates alkaline soils better than many other evergreens, which is useful in areas with high-pH soil.
Space the tree properly. If you plant it as a hedge, place plants 3 to 4 feet apart for a dense screen. As a standalone specimen, give it at least 8 to 10 feet of clearance from buildings or other large plants so it can develop its natural shape.
What Are The Best Growing Conditions?
Platycladus orientalis is a tough plant once established. It handles heat well and is notably drought-tolerant after its roots are established, which usually takes one to two growing seasons. It also tolerates cold down to about -10°F when fully dormant, though harsh winter winds can cause some bronzing or browning of the foliage.
Water deeply but less often. For the first year, water once or twice a week during dry spells. After that, the tree generally survives on natural rainfall in most regions. Overwatering is a more common problem than underwatering for this species.
Fertilizer is rarely necessary. A slow-release evergreen fertilizer in early spring can help a tree growing in poor soil, but healthy trees in average soil do not need it. Too much fertilizer can cause weak, fast growth that is more prone to damage.
How Do You Plant And Care For It?
Plant in early spring or fall when temperatures are mild. Dig a hole that is twice as wide as the root ball but no deeper. The top of the root ball should sit level with the surrounding soil. Planting too deep is a common error that can kill the tree slowly over several years.
Backfill with the original soil. Do not add compost or other amendments to the hole unless your soil is extremely poor. Studies have shown that trees planted in unamended soil often establish better because the roots grow out into the native soil instead of circling in the rich planting hole.
Mulch around the base with 2 to 3 inches of wood chips. Keep the mulch a few inches away from the trunk to prevent moisture buildup against the bark. This mulch layer conserves soil moisture and keeps roots cooler in summer.
Pruning is optional. This tree has a naturally neat shape. If you need to control size or shape a hedge, prune in early spring before new growth begins. Avoid cutting into old wood without foliage because evergreen branches do not reliably regrow from bare wood.
How Can You Tell It Apart From Similar Evergreens?
Several plants look similar at first glance. The key identifier for Platycladus orientalis is the vertical orientation of its foliage sprays. Most other arborvitae species, like the American arborvitae (Thuja occidentalis), hold their flattened sprays in horizontal or random directions. The vertical, fan-like arrangement is a reliable visual clue.
Another distinguishing feature is the small, fleshy cones. Platycladus orientalis produces cones that look somewhat like tiny, knobby berries when young. True Thuja species produce smaller, woody cones that open to release seeds.
The scent is also different. Crush a few leaves between your fingers. Platycladus orientalis has a milder, less pungent aroma than many other junipers and arborvitae species. This is not a definitive test, but it can support other identification clues.
What Are The Common Problems To Watch For?
Bagworms are the most common pest. These caterpillars build protective bags of foliage and silk on the branches. Severe infestations can defoliate a tree. Hand-picking the bags in fall or winter, when the eggs are inside, is an effective control for small infestations.
Root rot is the most serious disease issue. It happens when the soil stays excessively wet. Yellowing foliage, dieback of branches, and a general decline are signs. Prevention through proper drainage is the best approach because root rot is difficult to treat once established.
Winter burn causes browning on the windward side of the tree. This happens when cold, dry winds pull moisture from the leaves faster than the roots can replace it through frozen soil. Planting in a sheltered location or providing a windbreak can reduce this damage.
How Fast Does It Grow And How Long Does It Live?
This is a slow to moderate grower. Expect about 6 to 12 inches of new growth per year under good conditions. Some compact cultivars grow even slower. This slow rate means it requires less pruning than faster-growing evergreens.
With proper care, Platycladus orientalis is a long-lived tree. Many specimens live 50 to 100 years or more in cultivation. Ancient specimens in China are known to be several centuries old. The main threats to its lifespan are poor drainage, severe drought during establishment, and mechanical damage from lawn equipment.
Are There Good Cultivars For Home Landscapes?
Several named cultivars offer different sizes and colors. ‘Aurea Nana’ is a compact, golden-yellow form that stays around 4 to 6 feet tall. ‘Beverleyensis’ has bright golden foliage and a narrow, columnar shape. ‘Blue Cone’ offers blue-green foliage and good cold hardiness.
These cultivars maintain the same general care requirements as the species. Choose a cultivar based on the space you have and the color you prefer. Check the mature size before planting because dwarf labels sometimes refer to slower growth rather than a small final size.
Frequently Asked Questions
Is Platycladus orientalis the same as Thuja orientalis?
Yes, they are the same plant. Botanists reclassified it from the Thuja genus into its own genus, Platycladus, but the old name still appears in many nurseries and older references.
Can Platycladus orientalis grow in pots?
Yes, smaller cultivars grow well in containers for several years. Use a pot with drainage holes, well-draining potting mix, and water when the top inch of soil feels dry. Repot every 2 to 3 years as the roots fill the container.
Why is my Platycladus orientalis turning brown in winter?
This is usually normal winter bronzing, a natural response to cold temperatures. The foliage often turns a copper or bronze shade and reverts to green in spring. If the browning is only on one side or is severe, winter wind damage or a root problem may be the cause.
Does Platycladus orientalis attract deer?
Deer generally avoid this plant. Its dense foliage and aromatic oils make it less palatable than many other landscape plants. In areas with heavy deer pressure, no plant is completely safe, but this species is not a preferred food source.
