Ray Hartman ceanothus

Sun

Full sun; tolerates light afternoon shade, especially in hot inland gardens.

Water

Water deeply during establishment, allowing the soil to dry partly between waterings. Once established, water occasionally during prolonged drought; avoid frequent summer irrigation.

Soil

Well-drained soil, including sandy, loamy or stony ground. Tolerates clay if drainage is good, but struggles in waterlogged soil.

Height

15-20 ft (4.6-6.1 m)

Spread

10-20 ft (3-6.1 m)

Flowers

Medium-blue to violet-blue flower clusters in spring, sometimes continuing into early summer.

Foliage

Evergreen. Broad, oval, glossy dark-green leaves with toothed edges and paler undersides.

Growth

Fast

Care needed

Low

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

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

Difficulty

Hard

Toughness

Fairly tough

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

1. Planting day

   2.1 ft (0.64 m)

2. After 1 year

   7 ft (2.1 m)

3. After 2 years

   12 ft (3.5 m)

4. After 3 years

   16 ft (5 m)

5. After 5 years

   18 ft (5.4 m)

   full size

About 3 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

Mildly toxic: may upset a stomach

Growth rate

Fast

• Plant in autumn in mild climates, or spring where winters are colder, leaving room for its full width.
• Water deeply through the first one or two dry seasons; let the upper soil dry before watering again.
• Keep it away from frequently watered lawns and beds.
• Apply a light mulch over the root area, keeping it clear of the trunk and main stems.
• Avoid routine feeding; rich soil and heavy fertilising encourage soft growth.
• Choose a sheltered position away from cold, drying winds near the colder end of its range.

Pruning. Prune lightly just after flowering, shortening leafy shoots to maintain shape; avoid cutting into bare old wood, which may not regrow. To develop a small tree, gradually remove selected lower branches while the plant is young.

Spring

Plant in colder districts once severe frost has passed, and water the root ball thoroughly.

Late spring

After flowering, lightly shorten wayward shoots and remove dead or damaged branches.

Summer

Check new plants for dry root balls; water deeply when needed rather than little and often.

Autumn

Plant in mild-winter districts while the soil is still warm and seasonal rain is returning.

Winter

Check that water drains freely around the roots and remove any storm-broken branches.

• Use as an informal evergreen screen where its full width can develop without regular clipping.
• Train as a small multi-stemmed tree beside a terrace, leaving room for the spreading crown.
• Place behind low drought-tolerant perennials so its blue flowers form a spring backdrop.
• Combine with California native shrubs and grasses in a dry wildlife garden.

Garden styles it suits: California native, Mediterranean, Desert / xeriscape, Wildlife garden, Pollinator garden and Low-maintenance.

Plant it with: Manzanita, California sagebrush, Cleveland sage, California fuchsia, Deer grass and Rock rose.

Wildlife: Flowers provide abundant pollen and nectar for bees and other insects. The dense evergreen branches offer shelter and potential nesting cover for small birds.

• Root and crown rot in wet soil: improve drainage before planting, keep the crown above surrounding soil level and avoid frequent irrigation.
• Frost scorch or branch dieback: choose a sheltered site and wait until spring growth reveals which wood is dead before pruning.
• Scale insects: inspect stems and leaf undersides; remove small infestations by hand and use a labelled horticultural oil if necessary, avoiding flowers and hot weather.
• Poor recovery after hard pruning: retain leafy growth on branches and replace an overgrown plant rather than cutting it back to bare stumps.

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

• Blue blossom (Ceanothus thyrsiflorus)

  Often has narrower leaves than 'Ray Hartman', though forms vary considerably and flowering plants can be difficult to distinguish without a reliable label.

• Dark Star ceanothus (Ceanothus 'Dark Star')

  Has much smaller, closely packed leaves, darker blue flowers and a denser, generally smaller habit.

• Julia Phelps ceanothus (Ceanothus 'Julia Phelps')

  Has small, distinctly wrinkled leaves and deep violet-blue flowers, rather than the broad leaves and more open growth of 'Ray Hartman'.

The cultivar name honours Californian nurseryman Ray Hartman, and the common name California lilac refers to the lilac-like flower clusters rather than a relationship to true lilacs.

Propagation. Take semi-ripe cuttings in summer and root them in a free-draining medium with gentle humidity. Seed does not reliably produce plants identical to 'Ray Hartman'.

Accepted botanical name

Ceanothus

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