Japanese Hornbeam is a small to medium-sized, slow-growing, deciduous, understory tree. The tree grows up to 20-30 feet tall in cultivation and up to 50 feet tall in its native habitat. It is stately and sturdy with attractive foliage and ornamental catkins. The numerous pairs of deep veins on each leaf make the foliage distinctive. This tree serves well as an understory tree because of its tolerance to heavy shade. The Japanese Hornbeam is a member of the Betulaceae or Birch family. The tree is native to central and southern Japan and was introduced in 1895. The genus name, Carpinus, is Latin for "hornbeam." The species name, japonica, references its place of origin. The common name, Hornbeam, is derived from "horn," meaning hard, and "beam", meaning tree in Old English. Japanese Hornbeam is a low-maintenance tree and prefers partial shade to full shade. It will tolerate full sun. It is also tolerant of a wide range of soil types. This plant is propagated by seeds, softwood cuttings, or grafting. The bark is grayish-brown and has shallow furrows. The leaves are dark green, simple, and ovate to oblong in shape, with rounded or slightly cordate bases. They have prominent veining that gives the leaf a quilted appearance. The margins are doubly toothed. The flowers are male and female yellowish-green colored catkins. The male catkin has narrowly ovate pointed scales. The female catkin is slender with overlapping bracts that are toothed and ovate. Flowering occurs in spring. The female catkin produces a small roundish brown nutlet from late summer to fall. Japanese Hornbeam has a graceful form and attractive foliage. This plant would add interest to a lawn or as a low-maintenance understory tree. Insects Diseases, and Other Plant Problems: This tree has no serious pests or disease issues. Caterpillars and aphids may be seen. Powdery mildew, leaf spots, cankers, and twig blight can occur.
Curated pairwise relationships between this plant and others in the library — who feeds
whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.
No curated interactions recorded for this species yet.
Also noted by NC State
Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell
apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.
Deep shade (Less than 2 hours to no direct sunlight) | Full sun (6 or more hours of direct sunlight a day) | Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
Clay; High Organic Matter; Loam (Silt); Sand
Soil pH
Acid (<6.0); Alkaline (>8.0); Neutral (6.0-8.0)
Soil drainage
Good Drainage | Moist
Available space
24-60 feet
Mature size
Height: 20 ft. 0 in. - 30 ft. 0 in. | Width: 20 ft. 0 in. - 30 ft. 0 in.
Growth rate
Slow
Maintenance
Low
Canopy layer
2 - Understory (15-40 ft)
Form & Appearance
Habit / form
Pyramidal; Rounded
Texture
Medium
Foliage
Deciduous
Leaf color
Green
Leaf type
Simple
Leaf arrangement
Alternate
Leaf shape
Oblong; Ovate
Leaf margin
Doubly Serrate
Leaf feel
Smooth; Waxy
Leaf value
Showy
Leaf size
3-6 inches long, 1-3 inches wide
Hairs present
Yes
Leaf detail
The dark green leaves measure 2 to 4.5 inches long and 3/4 inch to 1 3/4 inches wide. They are ovate to oblong with a cordate or sometimes, a rounded base. The margins are doubly-toothed. The upper surface of the leaf has 20 to 24 prominent veins that give the leaf a quilted appearance. The leaf is downy along the mid-rib. The undersides of the leaf are a paler green color and downy along the veins and mid-rib.
Fall color
Gold/Yellow; Insignificant
Flower color
Cream/Tan; Gold/Yellow; Green
Flower form
Catkin
Flower size
1-3 inches
Flower detail
The flowers are male and female yellowish-green catkins that become pale brown as it matures. The male catkin is 1 to 2 inches long with an ovate and pointed 1/4 inch scales. The female catkin is 2 to 2.5 inches long with overlapping bracts. The bracts are toothed, ovate, and measure 5/8 to 7/8 inches long. They bloom in mid to late spring.
Bloom time
Spring
Fruit color
Brown/Copper
Fruit type
Nut
Fruit value
Showy
Fruit size
< 1 inch long, < 1 inch wide
Fruit detail
The fruit is a small ribbed nutlet that is attached to a serrated and folded bract. The bracts are on a sausage-shaped, 2 to 3 inch long hanging cluster. The fruits ripen in early fall and are dispersed during the winter.
Bark color
Light Brown; Light Gray
Bark detail
On young trees, the bark is grayish-brown, thin, and smooth. Later, the bark splits into shallow furrows. The tree has a fluted trunk.
Stem color
Brown/Copper; Red/Burgundy
Stem detail
The twigs are slender, smooth, and reddish-brown. Young shots have fine hairs. The twigs have vertical lenticels. The buds are initially green and then turn light brown in color and are cone-shaped.