Thujopsis dolabrata aka Deerhorn Cedar

Thujopsis dolabrata is an evergreen conifer in the cypress family. Gardeners also call it hiba or hiba arborvitae. It comes from moist forests in central and southern Japan. In gardens, it reaches 30–50 feet (9.1–15.2 metres) tall. Its spread is about 15–25 feet (4.6–7.6 metres). Reports of wild height range from 100–125 feet (30.5–38.1 metres). Growth is slow, and maturity can take 20–50 years. The crown forms a dense cone with upward-curving branch tips. Some trees stay shorter and take a shrub-like form.

The bark ranges from gray to reddish brown. It peels away in strips that run along the trunk. Flat branchlets hold the leaves in broad, level sprays. Young shoots start green, then turn brown as they age. The small, scale-like leaves grow in opposite pairs. Each pair sits at right angles to the next. Leaves feel thick and fleshy, with a glossy green surface. White stomatal bands mark their undersides. This species bears seed cones rather than showy flowers. Small brown cones sit alone at branch tips. They reach about three-quarters of an inch and ripen in fall.

Grow hiba in sun or part shade, not full shade. Light afternoon shade helps in places with hot summers. Keep the soil moist, but make sure water drains away. Loam suits it well, though RHS lists several soil types. Sources differ on the best soil pH for this tree. NC State favors acid to neutral soil. Missouri Botanical Garden favors neutral to alkaline loam. RHS accepts acid, neutral, and alkaline soils. The tree does not cope well with drought. Shelter it from wind, and avoid exposed planting sites. Its listed hardiness spans USDA zones 5–7 and RHS H6.

Give this tree room for its full height and width. Its dense crown can form a hedge or screen. It also suits lawns, woodland settings, and gardens with an Asian theme. The green foliage keeps its color through the year. Its crown offers shelter for wildlife. RHS says it needs no routine pruning. Seeds and semi-hardwood cuttings offer two ways to raise new plants.

Serious pest and disease trouble is uncommon, but damage can occur. Leaf blight can cause spots and leaf loss. Canker and leaf miners may also affect the tree. Other pests include bagworms, scales, mealybugs, and spider mites. Wind exposure can leave foliage yellow-brown after winter. Heavy snow and ice may break branches or stems.