How to Grow Ceanothus Arboreus - Plant Care & Tips

By NorwichGardener Team   /   2024

Ceanothus arboreus is a plant that is native to California. It is also known as the tree anemone. This plant grows to a height of 10-15 feet and has a spread of 6-8 feet. The leaves are dark green and glossy, and the flowers are white or pale blue. The fruit is a blackberry-like drupe.

How to Grow Ceanothus Arboreus - Plant Care & Tips

Alternative name

  • Mountain mahogany
  • Tree ceanothus
  • Island cedar
  • Torrey pine
  • Santa Cruz Island ironwood

Basic info

  • Ceonothus arboreus is a species of evergreen shrub or small tree in the buckthorn family, Rhamnaceae.
  • It is native to southwestern North America in the United States (Arizona, California, Colorado, Nevada, New Mexico, Utah) and northern Mexico (Baja California, Baja California Sur, Chihuahua, Coahuila, Durango, Sonora, Zacatecas).
  • It is commonly known as tree lilac, mountain lilac, or ash-leaved lilac.
  • The specific epithet arboreus means "tree-like".
  • Ceonothus arboreus typically grows to 2–10 m (6–38 ft) tall.
  • It has dark green, oval-shaped leaves 3–8 cm (2–1 in) long and 2–4 cm (0.79–57 in) wide.
  • The flowers are white or pale blue, borne in clusters 4–8 cm (6–1 in) long.
  • The fruit is a dry, brown capsule 5–7 mm (0.20–0.28 in) long containing small seeds.
  • Ceonothus arboreus is drought-tolerant and requires little maintenance.
  • It is often used as an ornamental plant in gardens and landscapes.

Planting Process

  1. For ceanothus arboreus, first step is to find a sunny spot in your garden.
  2. Then, dig a hole twice the size of the pot that the plant is currently in.
  3. Place the plant in the hole and backfill with soil.
  4. Water the plant deeply and regularly for the first growing season.
  5. Once the plant is established, reduce watering to once a week.
  6. Fertilize the plant in early spring with a balanced fertilizer.
  7. Prune the plant in late winter to early spring to shape as desired.
  8. To propagate, take stem cuttings in spring or summer.
  9. Watch for pests and diseases and treat as necessary.
  10. Enjoy your beautiful ceanothus arboreus plant!

Related plant:
Ceanothus Blue Mound

Soil Condition

About soil condition, it prefers well-drained soils, but it is not drought tolerant and will require supplemental irrigation in hot summer weather. The tree will also benefit from periodic deep watering and mulching to keep the roots cool and moist.

Light condition

Just like other Californian native plants, the Coastal California Blue Bush (Ceanothus arboreus) has low water requirements and prefers full sun. The sun not only dries out the bush's leaves, but it also helps produce the bush's unique blue color. If you live in an area with high summer temperatures, this bush is a perfect choice for your landscape.

Good Temperature

The temperature condition of the ceanothus arboreus is warm. It cannot tolerate cold temperatures and will suffer frost damage if exposed to them. It is best to grow this plant in an area that receives full sun and has well-drained soil.

Ideal Humidity

Ideal humidity condition for this plant is around 50%. They are drought resistant and do not need too much water. Too much water can actually be harmful to them. They do like moisture in the air though so a humidifier can be beneficial.

Fertilizer Requirement

The fertilizer, usually the plant food, is a mainstay in the growth and development of the (ceanothus arboreus). The root is the part of the plant that helps to secure and support the plant in the soil. It also helps to anchor the plant and absorb water and nutrients from the soil.

About light

Pruning is a vital part of keeping your California lilac (Ceanothus arboreus) looking its best. This tough, fast-growing shrub can quickly become overgrown and leggy if left unpruned. Luckily, pruning is easy to do and California lilacs respond well to being cut back. For the best results, prune your California lilac in late winter or early spring, before new growth begins.

Plant Propagation

Propagation is best done through seed, as cuttings may be difficult to root. Sow the seeds in a cold frame in late winter or early spring. scarify the seeds by nicking the seed coat with a sharp knife. This will help the seed to germinate. Plant the seeds 1/4 inch deep in a well-drained seed starting mix. Keep the soil moist but not wet and the seeds should germinate in 21-28 days. Once the seedlings are large enough to handle, transplant them into 4-inch pots. transplant them into the garden in the spring after all danger of frost has passed.

Growth Speed

Usually, the plant growth rate during the spring and summer, when the plant is actively growing. However, some plants may continue to grow during the fall and winter months. The plant's growth rate is determined by the amount of sunlight, water, and nutrients available to the plant.

Basic Problems

Common problems for this kind of plant are stem and root rots, and aphids. Stem and root rots can be caused by different fungi, including Pythium and Phytophthora. These fungi can be a problem in wet or poorly drained soils. Aphids are small, soft-bodied insects that can suck the sap out of plants. They are usually found in large numbers on new growth.

List to Know

  • Make sure to plant your ceanothus arboreus in an area that receives full sun.
  • This plant prefers well-drained soils, so make sure to plant it in a spot that has good drainage.
  • To encourage growth, water your plant regularly and fertilize it every few weeks.
  • Once your plant reaches about 2 feet tall, you can begin pruning it to encourage a fuller, more compact growth.
  • When the weather turns hot, make sure to provide extra water to your ceanothus arboreus.
  • If you live in an area with high winds, it's important to stake your plant to prevent it from blowing over.
  • Once your plant is established, it's relatively drought-tolerant and doesn't need as much water.
  • To encourage more blooms, deadhead spent flowers regularly.
  • If you live in an area

Similar Plants

  • Ceanothus 'furys blue'
  • Ceanothus 'fractus'
  • Ceanothus 'frosty morn'
  • Ceanothus 'fru'
  • Ceanothus 'fru'
  • Ceanothus 'fru'
  • Ceanothus 'fru'
  • Ceanothus 'fru'
  • Ceanothus 'fru'
  • Ceanothus 'fru'

Ceanothus 'Dark Star' | Landscape Plants - Oregon State University
Ceanothus americanus - North Carolina State University
Marie Simon ceanothus | UC Davis Arboretum and Public Garden

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Reviewed & Published by Richelle
Submitted by our contributor
Shrubs Category