Ceanothus purpureus

Hollyleaf Ceanothus

a perennial woody evergreen member of the Ceanothus genus in the family Rhamnaceae.

No photo available

Taxonomy and growth

Life cycle
perennial
Foliage
evergreen
Woodiness
woody
Height
2 m
Fertility
Bees
Flower type
hermaphrodite
Pollinators
Bees

Uses

Material uses

This section contains historical Plants For A Future notes marked noncommercial.

A green dye is obtained from the flowers[3]. All parts of the plant are rich in saponins - when crushed and mixed with water they produce a good lather which is an effective and gentle soap[3][4]. This soap is very good at removing dirt, though it does not remove oils very well. This means that when used on the skin it will not remove the natural body oils, but nor will it remove engine oil etc[K] The flowers are a very good source, when used as a body soap they leave behind a pleasant perfume on the skin[K]. The developing seed cases are also a very good source of saponins[K]. The spreading forms of this species make a useful ground cover, especially on warm sunny slopes[6].

Product or use
Dye
Product or use
Soap

Ecology and functions

Ecosystem niche
Soil surface

Ground cover

Nitrogen fixer

Environment

Range
South-western N. America - California.
Habitat
Dry rocky hills below 550 metres[10].
Light
full sun
Shade tolerance
light shade
Water
moderate
Hardiness
Zone 8+
Soil textures
sandy, loamy
Soil pH
acid, neutral, alkaline
Drainage
well drained
Tolerates Nutritionally Poor Soil
No
Drought
intolerant

Propagation

This section contains historical Plants For A Future notes marked noncommercial.

Seed - best sown as soon as it is ripe in a cold frame. Stored seed should be pre-soaked for 12 hours in warm water and then given 1 - 3 months stratification at 1°c[2][6]. Germination usually takes place within 1 - 2 months at 20°c[2]. One report says that the seed is best given boiling water treatment, or heated in 4 times its volume of sand at 90 - 120°c for 4 - 5 minutes and then soaked in warm water for 12 hours before sowing it[8]. The seed exhibits considerable longevity, when stored for 15 years in an air-tight dry container at 1 - 5°c it has shown little deterioration in viability[8]. The seed is ejected from its capsule with some force when fully ripe, timing the collection of seed can be difficult because unless collected just prior to dehiscence the seed is difficult to extract and rarely germinates satisfactorily[8]. Prick out the seedlings into individual pots as soon as they are large enough to handle. Grow them on in the greenhouse for at least their first winter and plant them out into their permanent positions in late spring or early summer. Plants usually produce an abundance of seed in British gardens[1]. Cuttings of half-ripe wood, taken at a node[6], July/August in a frame[1]. This species is difficult to root[6]. Cuttings of mature wood of the current year's growth, 7 - 12 cm with a heel, October in a cold frame[11]. The roots are quite brittle and it is best to pot up the callused cuttings in spring, just before the roots break[11]. This species is difficult to root[6].

Cultivation

This section contains historical Plants For A Future notes marked noncommercial.

Prefers a warm sunny position but tolerates light shade[1][6]. Requires a well-drained soil[1]. Tolerates some lime, but will not succeed on shallow chalk[6]. Plants are not fully hardy at Kew Botanical Gardens, though they succeed outdoors to the south and west of London[1]. Plants dislike root disturbance, they should be planted out into their permanent positions whilst still small[5]. Dislikes heavy pruning, it is best not to cut out any wood thicker than a pencil[5]. Plants flower on the previous year's growth, if any pruning is necessary it is best carried out immediately after flowering has finished[6]. Constant pruning to keep a plant small can shorten its life[6][9]. Fast growing, it flowers well when young, often in its second year from seed[1]. Hybridizes freely with other members of this genus[6]. Some members of this genus have a symbiotic relationship with certain soil micro-organisms, these form nodules on the roots of the plants and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby[6][7].

References

  1. Bean. W. Trees and Shrubs Hardy in Great Britain. Vol 1 - 4 and Supplement. Murray 1981-00-00

  2. Bird. R. (Editor) Growing from Seed. Volume 3. Thompson and Morgan. 1989-00-00

  3. Grae. I. Nature's Colors - Dyes from Plants. MacMillan Publishing Co. New York. 1974-00-00 ISBN 0-02-544950-8

  4. Buchanan. R. A Weavers Garden.

  5. Thomas. G. S. Ornamental Shrubs, Climbers and Bamboos. Murray 1992-00-00 ISBN 0-7195-5043-2

  6. Huxley. A. The New RHS Dictionary of Gardening. 1992. MacMillan Press 1992-00-00 ISBN 0-333-47494-5

  7. Craighead. J., Craighead. F. and Davis. R. A Field Guide to Rocky Mountain Wildflowers The Riverside Press 1963-00-00 ISBN 63-7093

  8. Matthews. V. The New Plantsman. Volume 1, 1994. Royal Horticultural Society 1994-00-00 ISBN 1352-4186

  9. Grey-Wilson. C. & Matthews. V. Gardening on Walls Collins 1983-00-00 ISBN 0-00-219220-0

  10. Munz. A California Flora. University of California Press 1959-00-00

  11. Sheat. W. G. Propagation of Trees, Shrubs and Conifers. MacMillan and Co 1948-00-00

Edit this page