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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.  

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 americanus The information on this webpage is based on research conducted about this plant in our nursery library, from online sources, as well as from observations made of it as it grows in the nursery in containers, in the nursery's garden and in other gardens where we have observed it growing. We will also incorporate comments received from others and welcome getting feedback from those who may have additional information, particularly if this information includes cultural information that would aid others in growing  Ceanothus 'Cynthia Postan'.