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California Lilac 'Umpqua Sky'

  • Scientific Name: Ceanothus thyrsiflorus 'Umpqua Sky'
  • Garden: Natives Garden
  • Plant Type: Tree
  • Evergreen/Deciduous: Evergreen
  • Sun/Shade Exposure: Full Sun to Part Shade
  • Moisture Requirements: Dry

Plant Information

A very large growing, vigorous and pretty tree type Ceanothus native to the extreme SW part of the state. This fast-growing evergreen tree (3′-4′ per year) puts on a huge display of soft blue flowers in late April to early June. Full sun to light shade (high overhead shade) and average soil that drains. Adaptable to clay soils, especially on slopes and not watered at all in summer. Completely drought adapted, no water necessary once established. To 18′ tall and half as wide in 7 years. Great screen, blue flowered tree that is beautiful in bloom but fades to a background for the rest of the year. Prodigious pruning can keep it much lower and it makes a great large hedge in no time. Good cold hardiness to 5ºF. We chose this variety in the wild because it was found quite a bit away from the coast which increases cold hardiness, and it was immensely heavy in bloom. Prune AFTER flowering if needed. As a hedge or smaller plant, it only requires pruning once a year- especially if strictly unwatered. Extraordinarily heavy bloomer and the trusses of flowers are often divided into six or more sub-branches for a very full look in bloom. Pairs well with Madrone and Arctostaphylos. Oregon native plant.

Biome: Hot Aspects, Low Water/No Water, Oregon Coast, Western Native
USDA Hardiness zone: Zn7b 10º to 5ºF
Foliage color: Dark Green
Foliage season: Evergreen

Data Source

Photo Credit

"CETH Full, CETH Flower (©2022 Cheri Moland)"