Acer japonicum 'O-isami'
Common Name: full moon maple 
Type: Tree
Family: Sapindaceae
Zone: 5 to 7
Height: 20.00 to 30.00 feet
Spread: 20.00 to 30.00 feet
Bloom Time: April
Bloom Description: Purplish-red
Sun: Full sun to part shade
Water: Medium
Maintenance: Low
Flower: Showy
Leaf: Good Fall
Tolerate: Rabbit, Black Walnut


Best grown in average, medium moisture, well-drained soil in full sun to part shade. Prefers lightly dappled shade. Leaves may scorch in full sun in hot southern summers. Plants prefer cool summer conditions. Site in locations protected from strong winds. Stake young trees for more erect growth. Plants perform poorly south of USDA Zone 7.

Noteworthy Characteristics

Acer japonicum, commonly called full moon maple, is a deciduous, spreading, small tree or large shrub that grows to 20-30’ tall. It often grows in a multi-trunked form. It is native to mountainous areas of Japan, Manchuria and Korea. It features rounded, palmate, almost fern-like, medium green leaves (to 3-6” across) which are deeply divided (approximately 1/3 of distance to the leaf base) into 7-11 acuminate, toothed and cut, ovate to lance-shaped lobes. Leaves turn yellow and red in fall. Each rounded leaf purportedly resembles a full moon, hence the common name. Small purplish-red flowers in pendulous corymbs appear in early spring (April) before the leaves. Flowers are followed by winged samaras (to 1” long) which ripen in late summer to early fall.

Genus name is the Latin name for a maple tree.

Specific epithet indicates native to Japan.

‘O-isami’ is an upright, large-leaved cultivar with an open rounded crown. It typically grows to 10' tall and 6' wide over the first 10 years, eventually maturing over time to 25-30' tall. Orbicular leaves (to 6" long and 7" wide) have 9-11 ovate-lanceolate lobes. Leaves emerge light green in spring, mature to a rich green by summer and finally turn bright shades of yellow, orange and red in fall. Each leaf measures about 4-5" across.


Foliage tends to leaf out early in spring and is subject to damage from late frosts. Susceptible to verticillium wilt, leaf spots, root rots, anthracnose, collar rot and stem canker. Potential insect pests include aphids, scale, borers and caterpillars. Mites may appear.


Grown primarily as a specimen or in small groups around the home, patio or yard. Vigorous understory tree featuring attractive foliage and stunning fall color.