Ceanothus, a wonderful blue flower shrub


Ceanothus is a tallish shrub that brings bees and butterflies to the garden in spring thanks to its magnificent blue flowers.

Key Ceanothus facts

Type – shrub

Exposure – full or part sun
Soil – any type is suitable
Flowering – March, April, May
or even summer for certain species

Foliage: evergreen  –  Height: from 6.5 to 16 feet (2 to 4m)

Ceanothus doesn’t require much care, at most a little pruning to keep it under control since it grows easily and produces abundant flowers!

How to plant Ceanothus

Proper exposure for Ceanothus

Full shade is too dark. Best plant your Ceanothus in a spot where it will get either full sun or part sun.

  • The more sunlight your ceanothus gets, the more flowers it will bear.

Best season to plant Ceanothus

Planting ceanothus properly means finding the right exposureSpring and fall are the two best times of year for planting Ceanothus. Avoid heat waves or days of frost.

  • Ceanothus will grow in any type of soil, but excess moisture will slow its growth. Ensure reasonable drainage.
  • Follow these simple shrub planting steps.

Ceanothus care and pruning

Deadheading Ceanothus

  • Removing dead flowers and dried up stems will trigger new blooms.

Pruning Ceanothus

Caring for ceanothus will enhance bloomingMake sure you get flowers on your ceanothus every year by pruning either in summer or fall. If you prune in spring, you’ll be cutting flower buds off. Don’t prune ceanothus at the end of winter.

Some Ceanothus species are deciduous. For these, control growth by cutting back branches that are a year old. Pruning last year’s growth will make your Ceanothus branch out and bear more flowers.

Watering Ceanothus

You won’t need to water your Ceanothus at all, except for the first two years.

  • You can even avoid this if you apply a thick layer of mulch at the base of the shrub.
  • Add hydrogel to the planting soil mix if your area is prone to drought.

Winter care for ceanothus

Ceanothus is rather hardy and must spend its life outside. It won’t thrive at all indoors.

Ceanothus is hardy down to about 14°F (10°C). If ever your area gets any colder, you’ll have to winterize your ceanothus.

Ceanothus growing in pots – winter care

It’s possible to grow Ceanothus in pots.

  • In that case, you can bring it in a greenhouse or lean-in.
  • It needn’t be very warm, simply keeping frost away is enough.
  • It does need to be well-lit, though.

Ceanothus outdoors – winter care

  • If temperatures often drop below 17°F or -8°C, wrap your Ceanothus bush with fleece.

Learn more about flowering Ceanothus

Ceanothus blueBlue is the color of most Ceanothus species. The shrub is covered in flower panicles in spring.

Other colors include pink and white, and various shades of violet.

Ceanothus is native to North America. It has successfully been introduced in many temperate climates.

  • Ceanothus can cope with growing along the seashore.
  • You can either let it grow as a thick hedge, as a standalone, or add it to a shrub bed.

Ceanothus and pollinators

Ceanothus is a favorite of pollinatorsBees and butterflies will be attracted by the wonderfully abundant flowers during the blooming.

Some varieties (essentially hybrids) bloom in summer and fall: Ceanothus × delileanus ‘Topaze’, Ceanothus × pallidus (like the ‘Perle Rose’), Ceanothus ‘Burkwoodii’ and Ceanothus arboreaus ‘Autumnal blue’, to name but a few.

Smart tip about Ceanothus

Ceanothus, commonly called soap bush and California lilac, also comes in ground-hugging varieties that are great to quickly cover rocky terrain!

Images: CC BY 2.0: Neil, CC BY-SA 3.0: Stan Shebs; Pixabay: Jacques Gaimard, Suzy Johns; Public Domain: United States Fish & Wildlife Service