1 named cultivar

‘Concha’Concha California Lilac

shrubN. America Native

Mountain Whitethorn

The Story

Plant Bio

Ceanothus cordulatus, or Mountain Whitethorn, is a spreading, thorny, evergreen shrub native to western North America. It features small, holly-like leaves and dense clusters of fragrant white flowers.

This species is exceptionally drought-tolerant and thrives on dry, rocky slopes, making it excellent for erosion control. Its thorny branches provide cover for wildlife.

Uses & Benefits:

Ceanothus cordulatus's vibrant blue flowers and evergreen foliage make it a striking addition to gardens and landscapes, providing year-round visual interest.

Its drought tolerance and low maintenance qualities make it ideal for xeriscaping and water-conserving landscapes.

Attracts pollinators like bees and butterflies, supporting local biodiversity.

Essentials

At a Glance

Plant Type

Shrub

Height

48 inches

Width

72 inches

Light

Full Sun, Partial Sun

Zones

6, 7, 8, 9, 10

Water

Low to moderate

Humidity

Prefers dry to moderate humidity

Lifespan

Decades with proper care

Native To

Western North America

Toxicity

Non-toxic

Planting

How to Grow

Tuck seeds into well-draining soil in early spring.
Mist cuttings regularly to maintain humidity for root development.
Transplant seedlings once established, typically after one year.
Fertilize lightly with a low-nitrogen fertilizer in spring.
Prune after flowering to maintain shape and remove dead wood.
Mulch around base to retain moisture and suppress weeds.

Pro Tip

Use well-draining, slightly acidic soil and provide full sun for best growth.

Keep It Thriving

Care Guide

Do

Water deeply during dry periods 🌱
Prune after flowering to shape the shrub
Apply a balanced fertilizer annually

Don't

Avoid overwatering to prevent root rot ❌
Don’t prune in late fall or winter
Refrain from using heavy, nitrogen-rich fertilizers

Seasonal Care Calendar

Task	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Fertilize
Mulch
Plant
Prune

Watch Out For

Pests & Diseases

Common Pests

Common Diseases

In the Garden

Landscape Uses & Companions

Landscape Uses

Wildlife-friendly borderDrought-tolerant slope plant

Companion Plants

Lavender EchinaceaRussian sage Sedum

Multiply

Propagation Methods

Good to Know

Common Questions

Mountain Whitethorn questions

What zones can Mountain Whitethorn grow in?

Mountain Whitethorn is hardy in USDA Zones 6–10. Inside that range it survives winter in the ground; outside it, grow it as an annual or a container plant you protect.

Is Mountain Whitethorn deer resistant?

Yes — Mountain Whitethorn is rated deer-resistant. Deer typically pass it over, though extreme hunger can override any plant's defenses.

When does Mountain Whitethorn bloom?

Mountain Whitethorn typically blooms in late spring to early summer through mid-spring. Exact timing shifts a week or two with your zone — Sow's bloom calendar maps it to your garden.

Does Mountain Whitethorn need full sun?

Mountain Whitethorn does best in full sun to part shade. In hot climates, afternoon shade keeps blooms fresher longer.

Is Mountain Whitethorn drought tolerant?

Yes — once established (usually after the first full season), Mountain Whitethorn handles dry spells with minimal watering. Water deeply its first year to build the root system that makes that possible.