Ceanothus L.

California Lilacs

Greek keanothus — classical name for spiny plants.

Deciduous and evergreen shrubs and small trees, sometimes spiny. Leaves variable, opposite or alternate, mostly toothed and with 3 prominent nerves arising from the base or veins pinnate. Flowers in terminal or lateral clusters, small, mostly blue but occasionally white to pink or violet. Sepals 5, united at the base. Petals 5, hooded, free. Stamens 5, opposite the petals. Ovary surrounded by a glandular disk. Fruit a 3- lobed capsule.

Grown for the range of pale to vivid blue flowers. Species hybridise readily in cultivation and deliberate crosses have produced some spectacular garden hybrids.

The introduction of many hybrids of uncertain parentage makes a key impractical.

About 55 species, most from W North America.

Cultivars by cuttings, species by cuttings and seed.

Leaves, fresh or dried, are used by American Indians as a tea and for other medicinal purposes.

Shrubs often with spectacular blue flowers, sometimes also with glossy leaves.

Gardiner (1997).

Source: Spencer, R. (2002). Rhamnaceae. In: Spencer, R.. Horticultural Flora of South-eastern Australia. Volume 3. Flowering plants. Dicotyledons. Part 2. The identification of garden and cultivated plants. University of New South Wales Press.

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Cultivars of uncertain parentage

Ceanothus 'Blue Cushion'

Compact, arching shrub to nearly 1 m tall and 1 m wide. Flowers mid-blue.

Ceanothus 'Edinburgh'

Upright shrub 2-3 m tall with glossy, dark leaves to about 7 cm long. Flowers prolific, deep blue; spring to early summer (C. griseus × ?C. papillosus).

Ceanothus 'Joyce Coulter'

Spreading shrub to about 1.5 m tall. Leaves to 2.5 cm long. Flowers clear blue in spikes generally more than 10 cm long.

Ceanothus 'Julia Phelps'

Densely branched shrub with small leaves. Flowers deep indigo in clusters to 2.5 cm long; spring.

Ceanothus 'Yankee Point'

Shrub to about 0.5 m tall and spreading to about 3 m wide. Flowers exceptionally prolific, bright clear blue.a cultivar of C. griseus var. horizontalis.

kingdom Plantae
phylum   Tracheophyta
class    Magnoliopsida
superorder     Rosanae
order      Rosales
family       Rhamnaceae
Higher taxa
Subordinate taxa
species         Ceanothus arboreus Greene
species         Ceanothus √ódelilianus Spach
species         Ceanothus gloriosus J.T.
species         Ceanothus papillosus Torr. & A.Gray