treeN. America Native

Coast Live Oak

The Story

Plant Bio

Quercus agrifolia, the coast live oak, is a broad-canopied evergreen tree native to the California Floristic Province, characterized by its short, stout trunk and heavy, crooked branches. The stiff, leathery leaves feature spiny, holly-like margins and a glossy dark green upper surface with pale, dull undersides.

This species is highly adapted to Mediterranean climates, producing yellow-green male catkins and small reddish-green female spikes in spring. New foliage emerges in late spring as older leaves are shed, maintaining a dense, year-round canopy that supports hundreds of native wildlife species.

Uses & Benefits:

Provides a massive, picturesque evergreen canopy with sculptural, twisting branches that serve as a dramatic focal point.

Offers excellent soil stabilization and erosion control on sloped sites, along with high coastal salt-spray tolerance.

Acts as a keystone species supporting over three hundred vertebrate species and hundreds of insect species with food and shelter.

Essentials

At a Glance

Plant Type

Tree

Height

984"

Width

984"

Light

Full Sun, Partial Sun

Zones

8, 9, 10

Water

Low

Humidity

Moderate

Lifespan

Long-lived

Native To

North America

Toxicity

Toxic if ingested

Bloom period

Spring

In flower about 3 months of the year

Planting

How to Grow

Select a planting site in full sun to partial shade with well-drained sandy loam, clay, or weathered granite soil.
Dig a hole twice as wide as the root ball but no deeper, ensuring the root crown sits slightly above the surrounding soil grade.
Water the newly planted tree deeply to settle the soil, and maintain moisture during its first two to three dry seasons.
Once established, cease all summer irrigation and avoid disturbing the soil within the tree's drip line.

Pro Tip

Never irrigate established trees during the summer months; introducing water to warm, dry soil triggers lethal crown rot and oak root fungus.

Keep It Thriving

Care Guide

Do

Prune exclusively during the dry summer months to minimize the risk of fungal infections.
Check the root system of nursery stock for circling roots before planting.
Allow fallen oak leaves to remain on the ground to form a natural, protective mulch layer.

Don't

Do not apply heavy nitrogen fertilizers, which stimulate weak, disease-susceptible growth.
Do not water established trees during the summer, especially in poorly drained soils.
Do not prune back into old, leafless wood, as epicormic sprouting is highly erratic.

Seasonal Care Calendar

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

Watch Out For

Pests & Diseases

Common Pests

Common Diseases

In the Garden

Landscape Uses & Companions

Landscape Uses

Specimen TreeShade TreeErosion ControlWildlife GardenWindbreak

Companion Plants

Arctostaphylos Ceanothus Salvia Heteromeles

Multiply

Propagation Methods

Good to Know

Common Questions

Coast Live Oak questions

What zones can Coast Live Oak grow in?

Coast Live Oak is hardy in USDA Zones 8–10. Inside that range it survives winter in the ground; outside it, grow it as an annual or a container plant you protect.

Is Coast Live Oak deer resistant?

Not reliably. Deer may browse Coast Live Oak, especially tender spring growth — plan on repellents or fencing where pressure is high.

When does Coast Live Oak bloom?

Coast Live Oak typically blooms in spring through spring. Exact timing shifts a week or two with your zone — Sow's bloom calendar maps it to your garden.

Does Coast Live Oak need full sun?

Coast Live Oak does best in full sun to part shade. In hot climates, afternoon shade keeps blooms fresher longer.

Is Coast Live Oak drought tolerant?

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