Larix kaempferi 'Diana'
Common Name: Japanese larch
Type: Tree
Family: Pinaceae
Zone: 4 to 7
Height: 20.00 to 25.00 feet
Spread: 10.00 to 13.00 feet
Bloom Time: Non-flowering
Bloom Description: Non-flowering
Sun: Full sun
Water: Medium
Maintenance: Low
Leaf: Evergreen
Other: Winter Interest

Culture

Best grown in rich, moist, acidic, well-drained soils in full sun. Tolerates some light shade. Intolerant of full shade, dry soils and most city pollutants. Best performance is in temperature conditions that mirror its native habitat, namely, cool summers and cold winters. Plants typically do not perform well in hot and humid summers south of USDA Zone 7.

Noteworthy Characteristics

Larix kaempferi, commonly called Japanese larch, is a deciduous conifer that is native to Japan. Bright green needles turn yellow in fall before falling to the ground in winter. In the wild, this larch species grows to 70-90' (less frequently to as much as 150') tall with a broad conical crown and horizontal branches. Green needles (to 1 1/2" long), each with two stomatal bands underneath, appear in brush-like clusters at the ends of spur-like shoots along the branches. Cones (to 1 1/2" long) with reflexed scales mature to brown. Bark is gray with rusty-brown inner bark. Needles turn gold in fall. Forestry tree in Japan and Europe.

Genus name is the classical name for larch trees.

Specific epithet honors Engelbert Kaempfer (1651-1716), German botanist and plant collector who visited Japan in the late 1600s.

'Diana' is a contorted cultivar that typically grows to 6-8' tall over the first 10 years, eventually maturing over time to 20-25' tall. Branches and stems are contorted and twisted. Twisted blue-green needles are soft to the touch. It was discovered by G. D. Boehlje near Westerstede, Germany in 1974.

Problems

Potential insect pests include larch case-bearer, larch sawfly, larch looper, tussock moth, Japanese beetle and woolly aphids. Potential disease problems include needle cast, needle rust and canker.

Garden Uses

Japanese larch is a large tree that should be planted in a sunny location with plenty of growing space. Good fall color. Bonsai.