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Products > Ceanothus 'Cynthia Postan'
Ceanothus 'Cynthia Postan' - Cynthia Postan Ceanothus

Note: This plant is not currently for sale. This is an archive page preserved for informational use.  
Image of Ceanothus 'Cynthia Postan'
Habit and Cultural Information
Category: Shrub
Family: Rhamnaceae (Buckthorns)
Origin: California (U.S.A.)
Evergreen: Yes
Flower Color: Blue
Bloomtime: Spring
Parentage: (C. papillosus v. roweanus x thyrsiflorus v. griseus)
Height: 6-8 feet
Width: 6-12 feet
Exposure: Full Sun
Irrigation (H2O Info): Low Water Needs
Winter Hardiness: 10-15° F
Ceanothus 'Cynthia Postan' (Cynthia Postan Ceanothus) - A dense shrub 6 to 8 feet tall and slightly wider with small, glossy, dark green leaves and violet blue flowers emerging from reddish buds in the late spring. The flowers can completely cover the plant at peak bloom. ‘Cynthia Postan’ is somewhat intermediate between two more commonly grown Ceanothus papillosus hybrids, Ceanothus 'Concha' and C. 'Wheeler Canyon'. It resembles 'Concha' more in form, although it is slower growing, and has flowers that are more aligned with those of 'Wheeler Canyon'. Plant in full sun. Little irrigation required. Plants along the coast have demonstrated considerable tolerance of heavy soils. Hardy to 10° F. We originally discovered this plant when investigating differences we had noted in plants being grown in the nursery trade labeled Ceanothus 'Wheeler Canyon.' We are thankful to Dave Fross at Native Sons Nursery for bringing this great cultivar to our attention. It was selected at the University Botanic Garden in Cambridge, England from seed collected by Lady Cynthia Postan from a plant of Ceanothus papillosus var. roweanus growing in the Regional Parks Botanic Garden in Berkeley, CA. The genus name comes from the Greek word keanthos which was used to describe a type of thistle and meaning a "thorny plant" or "spiny plant" and first used by Linnaeus in 1753 to describe New Jersey Tea, Ceanothus americanusInformation displayed on this page about  Ceanothus 'Cynthia Postan' is based on the research conducted about it in our library and from reliable online resources. We also note those observations we have made of this plant as it grows in the nursery's garden and in other gardens, as well how crops have performed in our nursery field. We will incorporate comments we receive from others, and welcome to hear from anyone who may have additional information, particularly if they share any cultural information that would aid others in growing it.