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Japanese Tree Lilac

Photos courtesy of J. Frank Schmidt & Son Co.

Scientific Name:
Syringa reticulate ‘Ivory Silk’

Other Common Names:
Giant Tree Lilac

Under Power Lines:
Yes—this tree is approved for planting under power lines.

Street Tree Planting:
Yes—minimum planting strip width of 5 feet. If planting a street tree, you must be approved for a permit.

Beautiful street or yard tree that works well under power lines. Tree provides a lovely show of white flowers in May to early June. The tree also has attractive reddish-brown bark for winter interest.

Mature Height:
25 feet

Mature Spread:
15 feet

Dark green leaves opening in early spring; no notable fall color.

Creamy white flowers in dense clusters from May to July, which share similarities with the lilac shrub’s flowers, but are not as fragrant. Flowers attract hummingbirds and butterflies.

Upright clusters of capsules.

Cultural Notes:
Tolerant of urban conditions, including poor clay or alkaline soils. Best grown in full sun, however tolerates part sun. The tree produces more brilliant blooms when planted in full sun with good drainage.

Potential Problems:
Overall, the tree is very pest and disease resistant, however regular watering is key to keeping the pests away in the summer. Trees planted in the shade are sometimes infected by powdery mildew especially in wet years, causing defoliation. Lilac borer can also be a problem, although planting the tree in the right spot and properly watering the tree through the summer will help keep the tree healthy.

Minimum Planting Distances:

  • 15 feet from house or building
  • 3 ½ feet back from the face of the curb
  • 5 feet from underground utility lines
  • 10 feet from power poles
  • 7 ½ feet from driveways (10 feet recommended)
  • 20 feet from street lights and other existing trees
  • 30 feet from street intersections

More Information:


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