Concha ceanothus

Sun

Full sun; choose a sheltered position away from cold, drying winds.

Water

Water regularly during establishment, allowing the soil surface to dry between waterings. Once established, water only during prolonged drought; frequent summer irrigation can cause root problems.

Soil

Well-drained, moderately fertile soil, including sandy or gravelly ground. Avoid waterlogged soil and heavy clay that stays wet through winter.

Height

6-10 ft (1.8-3 m)

Spread

6-12 ft (1.8-3.7 m)

Flowers

Deep cobalt-blue flower clusters in mid- to late spring, sometimes continuing into early summer; timing varies with climate.

Foliage

Evergreen. Small, oval, glossy dark green leaves with a slightly textured surface.

Growth

Fast when young, slowing as it matures.

Care needed

Low

• Pollinators
• Drought tolerant
• Heat tolerant
• Wildlife
• Low allergen

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Moderate

Toughness

Fairly tough

Pick your zone, country, light and whether you have pets.

1. Planting day

   1.6 ft (0.5 m)

2. After 1 year

   2.9 ft (0.88 m)

3. After 2 years

   4 ft (1.3 m)

4. After 3 years

   5 ft (1.6 m)

5. After 5 years

   8 ft (2.4 m)

   full size

About 5 years to full size.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Safe

Growth rate

Moderate

• Plant in spring in colder districts; autumn planting suits mild-winter areas with freely draining soil.
• Water deeply through the first growing season, then gradually reduce watering as roots establish.
• Do not routinely feed; rich soil and high-nitrogen fertiliser encourage soft growth.
• Keep mulch clear of the stem base and avoid moisture-retentive mulch on already damp soil.
• Give it room to reach its natural width rather than relying on repeated hard pruning.
• In colder gardens, use a sheltered, sun-facing wall and protect young plants during severe frosts.

Pruning. Immediately after flowering, lightly shorten long shoots within the leafy growth to maintain shape. Avoid cutting into old, bare wood, which often fails to regrow, and remove dead or damaged branches as needed.

Spring

Plant in colder districts once severe frost has passed, keeping the rootball intact.

Spring

Check for winter damage and remove clearly dead growth once new shoots reveal what has survived.

Late spring to early summer

After flowering, lightly trim wayward shoots without cutting into bare wood.

Summer

Check newly planted shrubs during dry spells and water deeply when the root zone begins to dry.

Late summer

Take semi-ripe cuttings from healthy, non-flowering shoots.

Autumn

Plant in mild-winter gardens with good drainage; keep fallen debris away from the stem base.

Winter

Check for standing water and protect young shrubs from severe frost and cold winds.

• Use as a broad evergreen specimen in a sunny border, allowing space for its arching branches.
• Train against a sheltered, sun-facing wall to bring blue flowers and evergreen cover to a courtyard.
• Combine with silver-leaved shrubs and drought-tolerant perennials in a gravel or Mediterranean garden.
• Plant as a loose informal screen in mild climates rather than clipping it as a tight hedge.
• Place near paths or seating where spring-flowering plants can support visiting bees.

Garden styles it suits: Mediterranean, California native, Coastal, Dry gravel garden, Pollinator garden and Desert / xeriscape.

Plant it with: Lavender, Rosemary, Rockrose, Santolina, California poppy and Bearded iris.

Wildlife: The flowers attract bees and other pollinating insects. Dense evergreen branches provide shelter for small birds.

• Root or crown rot: yellowing, wilting or sudden collapse can follow poor drainage or frequent irrigation. Improve drainage before planting, keep the crown clear and avoid watering established shrubs routinely.
• Frost and wind scorch: exposed leaves and shoots may brown after cold weather. Choose shelter, protect young plants and wait until spring growth starts before removing damaged shoots.
• Scale insects: inspect stems and leaf undersides if growth weakens or sticky deposits appear. Remove small infestations by hand; use a locally approved horticultural oil if necessary, following the label.
• Poor recovery after hard pruning: bare branches may not reshoot. Keep pruning light and replace a badly overgrown shrub rather than cutting it back severely.

Not known to be toxic to people, cats, dogs or horses. No part is recognised as seriously poisonous, but it is not an edible plant and eating foliage may cause digestive upset.

• Common lilac (Syringa vulgaris)

  Common lilac loses its leaves in winter and has much larger, usually heart-shaped leaves and strongly scented flower panicles; 'Concha' has small evergreen leaves.

• Gloire de Versailles ceanothus (Ceanothus × delileanus 'Gloire de Versailles')

  It is deciduous, with larger leaves and loose clusters of pale blue flowers mainly in summer and early autumn; 'Concha' is evergreen with denser, deeper blue spring flowers.

The common name California lilac refers to its Californian origins and lilac-like blue flower clusters, although ceanothus is not closely related to true lilacs.

Propagation. Take semi-ripe cuttings in late summer and root them in a free-draining medium with gentle humidity. Cuttings preserve the cultivar; seedlings will not reliably match 'Concha'. Avoid disturbing established roots.

Accepted botanical name

Ceanothus

Sources: GBIF (CC BY 4.0). The care and design notes are LandscapeGPT's own.