''Ceanothus thyrsiflorus'', known as blueblossom or blue blossom ceanothus, is an

evergreen In botany, an evergreen is a plant which has foliage that remains green and functional through more than one growing season. This also pertains to plants that retain their foliage only in warm climates, and contrasts with deciduous plants, which ...

shrub in the buckthorn family Rhamnaceae that is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

to Oregon and California in the US. The term 'Californian lilac' is also applied to this and other varieties of ceanothus, though it is not closely related to ''

Syringa ''Syringa'' is a genus of 12 currently recognized species of flowering woody plants in the olive family or Oleaceae called lilacs. These lilacs are native to woodland and scrub from southeastern Europe to eastern Asia, and widely and commonly ...

'', the true lilac.

Description

''Ceanothus thyrsiflorus'' can grow more than tall and broad in its native

chaparral Chaparral ( ) is a shrubland plant community and geographical feature found primarily in the U.S. state of California, in southern Oregon, and in the northern portion of the Baja California Peninsula in Mexico. It is shaped by a Mediterranean c ...

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

, with glossy green leaves. The clusters of tiny flowers, borne in spring, vary from different shades of blue to close to white. The evergreen leaves are shiny and about long.

Etymology

The Latin genus name ''Ceanothus'' is derived from the

Ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic peri ...

, (; 'spiny plant'). The name was originally used by

Theophrastus Theophrastus (; grc-gre, Θεόφραστος ; c. 371c. 287 BC), a Greek philosopher and the successor to Aristotle in the Peripatetic school. He was a native of Eresos in Lesbos.Gavin Hardy and Laurence Totelin, ''Ancient Botany'', Routledge ...

for another plant, and

Linnaeus Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the ...

reused it for ''Ceanothus''.Gledhill, David (2008). "The Names of Plants". Cambridge University Press. (hardback), (paperback). pp 96, 168, 379 The Latin

specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

''thyrsiflorus'' is derived from the Ancient Greek (; meaning a 'contracted panicle, wreath, or

thyrsos A thyrsus /ˈθɜːrsəs/ or thyrsos /ˈθɜːrˌsɒs/ (Ancient Greek: θύρσος) was a wand or staff of giant fennel ('' Ferula communis'') covered with ivy vines and leaves, sometimes wound with taeniae and topped with a pine cone, artich ...

') and the Latin ( gen. 'flower'), and so, ''thyrsiflorus'' means approximately 'with flowers arranged in the shape of a contracted panicle or thyrsos staff'.

Ecology

It is popular with birds, butterflies, and other

pollinator A pollinator is an animal that moves pollen from the male anther of a flower to the female stigma of a flower. This helps to bring about fertilization of the ovules in the flower by the male gametes from the pollen grains. Insects are the maj ...

s. It is often visited by honeybees for its

pollen Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophyt ...

Cultivation

''Ceanothus thyrsiflorus'' has been used in gardens extensively. It prefers a warm, sheltered position in full sun. Several

cultivars A cultivar is a type of Horticulture, cultivated plant that people have selected for desired phenotypic trait, traits and when Plant propagation, propagated retain those traits. Methods used to propagate cultivars include: division, root and st ...

have been selected, including: *'Blue Mound' which can grow to tall *'Cascade' which may reach of height *'El Dorado', a variegated cultivar with gold edge foliage and powder blue flowers *'Repens' which stays as a shrub around tall *'Repens Victoria', forming a sturdy evergreen mound and most useful groundcover with powder blue flowers *'Skylark', a tall type with blue flowers (this cultivar has gained the

Royal Horticultural Society The Royal Horticultural Society (RHS), founded in 1804 as the Horticultural Society of London, is the UK's leading gardening charity. The RHS promotes horticulture through its five gardens at Wisley (Surrey), Hyde Hall (Essex), Harlow Carr (Nort ...

Award of Garden Merit The Award of Garden Merit (AGM) is a long-established annual award for plants by the British Royal Horticultural Society (RHS). It is based on assessment of the plants' performance under UK growing conditions. History The Award of Garden Merit ...

) *'Snow Flurry', with white flowers

References

External links

CalFlora Database: ''Ceanothus thyrsiflorus'' (blueblossom)Jepson eFlora (TJM2): ''Ceanothus thyrsiflorus''''Ceanothus thyrsiflorus'' — U.C. Photo gallery
thyrsiflorus Endemic flora of California Flora of the Klamath Mountains Natural history of the California chaparral and woodlands Natural history of the California Coast Ranges Natural history of the San Francisco Bay Area Plants described in 1826 Taxa named by Johann Friedrich von Eschscholtz Butterfly food plants Garden plants of North America Drought-tolerant plants Flora without expected TNC conservation status {{Rhamnaceae-stub