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Giant Tree Lilac

Syringa reticulata (si-RING-ga re-tik-u-LA-ta)

Family: Oleaceae Unknown Understory (15-40 ft)

Japanese tree lilac is a small deciduous tree or large shrub in the olive family (Oleaceae). The tree is native to Japan and is found growing on cliffs. The species epithet, reticulata , means "netted veins" and refers to the plant's leaves. Plant in full sun in organically rich well-drained acidic soils. It will tolerate heavy clay soils and urban conditions along with browsing by deer. This tree will tolerate partial shade; however, full sun is required for prolific flower production. Good air circulation is also recommended. The Japanese tree lilac grows to a height of 30 feet tall and may be single or multi-stemmed with an oval to rounded canopy. The bark is reddish brown with distinctive, horizontal lenticels. The leaves are dark green, pubescent on their undersides and have a drooping habit. The flowers bloom in June and are borne in short, axillary panicles. The creamy-colored flowers are scented and last only 2 weeks. They lack the sweet fragrance typically associated with lilacs and have more of a privet-like odor (see Ligustrum lucidum ). The blooms are followed by clusters of green and then yellow capsules that can persist through winter. Its showy fragrant blooms attract hummingbirds, insect pollinators, and butterflies. The tree also provides shelter and habitat for wildlife. The Japanese tree lilac would be a nice addition to the patio area to provide flowers in the late spring to early summer and shade for the summer. It is the most trouble-free lilac . It may also be considered as a street tree, large hedge, or an accent or specimen for a shrub border. Quick ID Hints: the bark has prominent horizontal lenticels exfoliating, reddish-brown bark when young, and the bark becomes scaly and gray with age the leaves are dark green, simple, broad-ovate to ovate with sharp tips and a drooping habit the flowers are creamy-colored panicles measuring 6 to 12 inches long and bloom in June for 2 weeks the fruits are clusters of warty, dry, and green to yellow capsules that appear after the flowers and persist through the winter the buds have 4 pairs of scales and are brown and sessile Insects, Diseases, and Other Plant Problems : The Japanese tree lilac has no serious insect or disease problems. It tends to be resistant to powdery mildew, bacterial blight, scale insects, and borers. VIDEO created by Grant L. Thompson for β€œ Trees, Shrubs, and Woody Vines for Landscaping ” a plant identification course offered by the Department of Horticulture at Iowa State University .

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 64 attributes.

How it fits the guild

Guild layer 2 - Understory (15-40 ft) Optimal soil pH Acid (<6.0); Neutral (6.0-8.0)
See companions & conflicts ↓

Companions & Conflicts

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.

Often confused with Daphne genkwa Syringa reticulata subsp. amurensis Syringa reticulata subsp. pekinensis Syringa vulgaris
Fills a similar niche Buddleja alternifolia Petunia x hybrida Salvia rosmarinus

Full plant profile

Growing Conditions
Plant type
Perennial; Shrub; Tree
Life cycle
Woody
USDA zones
3a, 3b, 4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b
Light
Full sun (6 or more hours of direct sunlight a day)
Soil texture
Clay; High Organic Matter; Loam (Silt); Sand
Soil pH
Acid (<6.0); Neutral (6.0-8.0)
Soil drainage
Good Drainage | Moist
Available space
12-24 feet; 24-60 feet
NC region
Mountains; Piedmont
Mature size
Height: 25 ft. 0 in. - 30 ft. 0 in. | Width: 15 ft. 0 in. - 20 ft. 0 in.
Growth rate
Medium
Maintenance
Low
Canopy layer
2 - Understory (15-40 ft)
Form & Appearance
Habit / form
Dense; Erect; Multi-stemmed; Oval; Rounded
Foliage
Deciduous
Leaf color
Gray/Silver; Green
Leaf type
Simple
Leaf arrangement
Opposite
Leaf shape
Ovate
Leaf margin
Entire
Leaf size
3-6 inches long, 1-3 inches wide
Hairs present
Yes
Leaf detail
The leaves are dark green, simple, pubescent or smooth, and broad-ovate to ovate with sharp tips. The undersides of the leaf are grayish green. They measure 2 to 5.5 inches long and 1 to 3 inches wide and have an arching or drooping habit. The petiole is 1/2 to 1-inch in length. The leaves have no significant fall color.
Fall color
Insignificant
Flower color
Cream/Tan; White
Flower value
Fragrant; Good Cut; Showy
Flower form
Panicle
Flower detail
Creamy white fragrant flowers appear on upright panicles that measure 6 to 12 inches long. They bloom in June for about 2 weeks. The flowers have a musky, privet-like scent.
Bloom time
Summer
Fruit color
Gold/Yellow; Green
Fruit type
Capsule
Fruit value
Long-lasting
Fruit size
< 1 inch long, < 1 inch wide
Fruit detail
The flower blooms are followed by clusters of warty, dry, oblong, or ovoid capsules. They measure about 0.75 inches long and are initially green and then turn yellow. The capsules can persist through the winter.
Bark color
Dark Brown; Dark Gray; Red/Burgundy
Bark detail
The bark is smooth, reddish brown, and exfoliating with horizontal lenticels. As the tree ages, the bark becomes gray and scaly.
Stem color
Brown/Copper
Stem detail
The stems are stout, hollowed-out, and shiny brown.
Wildlife & Ecology
Native status
Unknown
Wildlife value
Flowers attract hummingbirds, insect pollinators, and butterflies.
Attracts
Butterflies; Hummingbirds
Play value
Attractive Flowers; Attracts Pollinators; Fragrance; Shade; Wildlife Cover/Habitat
Food & Medicine
Harvest time
Fall; Summer; Winter
Fruit type
Capsule
Landscape Use
Landscape location
Lawn; Patio
Landscape theme
Butterfly Garden; Cottage Garden; Cutting Garden; Pollinator Garden
Design feature
Flowering Tree; Foundation Planting; Hedge; Small groups; Small Tree; Specimen; Street Tree
Garden tags
#flowering tree #foundation planting #border planting #nectar plant #specimen #clay soils tolerant #small tree #hummingbird friendly #deer resistant #flowers early summer #showy flowers #interesting bark #summer flowers #white flowers #exfoliating bark #fragrant flowers #butterfly friendly #deck planting #salt tolerant #drought tolerant #landscape plant sleuths course #patio #wildlife friendly #hortcontest #screen #small groups
Problems & Resistance
Insect problems
Lilac Borer \ Ash Clearwing Borer; Pests of Lilac
Resistant to
Deer
Particularly resistant to
Powdery mildew, borers, scale
Propagation
Seed; Stem Cutting

Planted at Hunnicutt

Nobody’s planted this one yet.