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A picture of a Californian Lilac

Californian Lilac

Ceanothus spp.

Also known as

Wild Lilac, Soap Bush, Ceanothus, Redroot

Full Sun
Easy care
Moderate watering
Half-hardy

8a-9b

USDA zone

-12°C

Minimum temperature

Expected size

Height
Spread

6m

Max

8m

1m

Min

1.2m

5 years to reach maturity

Flowering

  • spring
  • summer
  • autumn
  • winter

This plant has a strong fragrance

More images of Californian Lilac

A photo of Californian Lilac
A photo of Californian Lilac
A photo of Californian Lilac
Ceanothus thyrsyflorus Repens
Ceanothus griseus var horizontalis 3

Californian Lilac Overview

Ceanothus is a genus with over 60 mostly evergreen shrub and small tree species. These beautiful plants are grown for their impressive display of tiny blue-purple, pink or white, occasionally fragrant flowers. The flowers appear spring, early summer or autumn, depending on which species you have. Ceanothus can be grown as free-standing trees or trained up against a wall, adding structure and colour to any garden. Their drought tolerance and low maintenance requirements make them a popular choice for Mediterranean-style or dry gardens. Many are commonly known by the name Californian Lilac, some plants in this genus go by the names California Lilac, Wild Lilac and Soap Bush. Ceanothus prefer a sunny sheltered spot with only a light annual prune. In exposed sites, Californian Lilacs can experience some frost damage so it is best to choose a deciduous cultivar that will not suffer as much. A member of the Rhamnaceae family, these plants are native to North America, where they grow in dry, hilly habitats, ranging from open forestland to coastal scrub. Although they are fast-growing, they can be short-lived.

Common problems with Californian Lilac

How to harvest Californian Lilac

Generally not harvested.

How to propagate Californian Lilac

Cuttings

Propagation through cuttings is considered moderately difficult. Semi-ripe cuttings may be taken from evergreen species from mid-summer through to autumn. Deciduous shrubs are better propagated from softwood cuttings, these may be taken from late spring through to mid-summer.

Seed

Ceanothus may be grown from seed, but they are difficult to germinate and many are unlikely to be true to type. To grow from seed, physical seed coat dormancy must be broken before successful germination. First, soak seeds in hot water for 24 hours, then cold stratify for up to 3 months. Following cold stratification, keep at 16-18 degrees Celsius and germination should occur within 3 months.

Special features of Californian Lilac

Attractive flowers

Hedge plant

Other uses of Californian Lilac

Grown for their small but densely clustered, mainly blue flowers. Attractive to bees.

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