Common Name: Japanese tree lilac
Type: Tree
Family: Oleaceae
Zone: 3 to 7
Height: 20.00 to 25.00 feet
Spread: 15.00 to 20.00 feet
Bloom Time: May to June
Bloom Description: Creamy white
Sun: Full sun to part shade
Water: Medium
Maintenance: Low
Suggested Use: Street Tree, Flowering Tree
Flower: Showy, Fragrant
Attracts: Hummingbirds, Butterflies
Other: Winter Interest
Tolerate: Deer, Clay Soil
Culture
Easily grown in average, medium moisture, well-drained soil in full sun. Tolerates light shade, but best bloom occurs in full sun. Prefers organically rich, moist, slightly acidic soils with good drainage. Needs good air circulation. Tolerates urban conditions well. To the extent practicable, faded flower panicles should be removed prior to seed set. Prune as needed immediately after flowering. Best growth typically occurs in cool summer climates. Not recommended for planting south of USDA Zone 7.
Noteworthy Characteristics
Syringa reticulata, commonly called Japanese tree lilac, typically grows as a small tree or large shrub. In tree form, it grows to 30’ tall and 20’ wide with an oval-rounded crown. Its best ornamental feature is its showy, fragrant, creamy white flowers which bloom in upright panicles to 12” long in late spring to early summer (later than most other lilac species). Some gardeners dislike the privet-like smell of the flowers. Flowers give way to loose clusters of brown capsules that persist into winter. Reddish-brown peeling bark is attractive on younger branches, gradually turning gray with age. Sharply-tipped, lanceolate to ovate, dark green leaves (to 6” long). No fall color.
Genus name comes from the Greek word syrinx meaning tube or pipe in reference to the pith-filled but easily-hollowed stems of some genus plants.
Specific epithet means netted-veined in reference to the leaf veins.
'Ivory Silk' is a small tree or large shrub which typically grows 20-25' tall with a rounded crown. Creamy white, fragrant, single flowers are arranged in dense, terminal clusters (panicles to 12" long). Blooms later than most other species of lilac (late May to early June in St. Louis). Elliptic to ovate, dark green leaves (to 5" long). Attractive reddish-brown bark.
Problems
No serious insect or disease problems. It reportedly has good resistance to some of the major pests of lilacs, such as powdery mildew, scale and borers. It has some susceptibility to additional diseases including blights, leaf spots, wilt and ring spot virus. Additional insect pests of note include caterpillars and leaf miner. Flower buds are susceptible to frost injury in early spring.
Uses
Effective as a specimen in the landscape. Tree forms are effective along streets, in lawns, near decks/patios or in foundations. Shrub forms are effective in borders or small groups. May be used as a screen along property lines.