How much water does California Black Oak need?

Once established, California Black Oak gets by on low water and handles dry summer conditions typical of oak woodlands. Occasional extra water can help young trees establish faster.

When does California Black Oak bloom?

It flowers in April and May, producing slender catkins before the new leaves fully expand.

Does California Black Oak keep its leaves year round?

No, it is deciduous and drops its lobed leaves in fall, leafing out again in spring.

How much sun does California Black Oak need to grow well?

It grows best in full sun but can also tolerate part shade, especially as a young tree under a partial canopy.

What insects visit the flowers of California Black Oak?

Bees and beetles are known to visit the catkins for pollen, although like other oaks it relies mainly on wind for pollination.

Is California Black Oak toxic to livestock?

The USDA PLANTS Database does not flag California Black Oak as toxic to livestock.

Is California Black Oak HOA-friendly?

California Black Oak is generally an HOA-friendly choice in the right placement, with moderate maintenance.

California Black Oak

Name: Pollinator Patch
Author: Pollinator Patch

Quercus kelloggii

Last reviewed: September 2026

California Black Oak is a deciduous tree that blooms in April and May, tolerates low water once established, and does well in full sun to part shade in oak woodlands and mixed conifer forests.

California Black Oak (Quercus kelloggii) is not on the ASPCA Animal Poison Control Center toxic plant list for dogs or cats (aspca.org (opens in new tab), last reviewed 2026-05-21). If your pet shows symptoms after eating any plant, call the ASPCA at (888) 426-4435.

The USDA PLANTS Database (opens in new tab) does not flag California Black Oak as toxic to livestock.

Light

full sun

Water

low

Size

144"–600" H × 240"–480" W

Bloom

Apr, May

Native to

CA, OR

Pollinators

bees, beetles

Before you buy

Your city may pay you to plant this

Cities and water utilities offer rebates for replacing lawn with native and water-wise plants. We track 452 programs across 44 states, each with a link to the provider and the date we last checked it.

Find rebates in your area

Browse plants for this ecoregion

Coast Range Marine West Coast Forest Northwestern Forested Mountains Sierra Nevada Central California Foothills and Coastal Mountains Central California Valley Southern California Mountains Central Basin and Range Southern California/Northern Baja Coast

A majestic, deciduous native tree that can reach heights of 12-50 feet with a broad, spreading canopy. It features distinctive lobed leaves that turn golden yellow to orange in fall before dropping. This oak blooms in spring with subtle catkins that later produce acorns.

Growing California Black Oak

Grow California Black Oak in full sun and low water. Mature plants reach 144 to 600 inches tall and spread 240 to 480 inches wide. Expect moderate maintenance to keep it looking intentional in a front yard.

In an HOA neighborhood

California Black Oak is an HOA-friendly choice in the right placement. Maintenance level: moderate. Tidiness: 3 out of 5.

Works well in: mid zone, street edge.

Extremely large mature size may conflict with HOA preferences
Leaf drop in fall requires seasonal cleanup
Acorn production can create maintenance concerns on hardscapes

Wildlife value

Host plant for California sister butterfly, California hairstreak.

This oak provides substantial habitat value, supporting bees and beetles with its spring blooms. Its acorns are a crucial food source for numerous wildlife species including birds, deer, and small mammals.

Common questions

How much water does California Black Oak need?: Once established, California Black Oak gets by on low water and handles dry summer conditions typical of oak woodlands. Occasional extra water can help young trees establish faster.
When does California Black Oak bloom?: It flowers in April and May, producing slender catkins before the new leaves fully expand.
Does California Black Oak keep its leaves year round?: No, it is deciduous and drops its lobed leaves in fall, leafing out again in spring.
How much sun does California Black Oak need to grow well?: It grows best in full sun but can also tolerate part shade, especially as a young tree under a partial canopy.
What insects visit the flowers of California Black Oak?: Bees and beetles are known to visit the catkins for pollen, although like other oaks it relies mainly on wind for pollination.
Is California Black Oak toxic to dogs?: California Black Oak is not on the ASPCA Animal Poison Control Center toxic plant list for dogs (aspca.org).
Is California Black Oak toxic to cats?: California Black Oak is not on the ASPCA Animal Poison Control Center toxic plant list for cats (aspca.org).
Is California Black Oak toxic to livestock?: The USDA PLANTS Database does not flag California Black Oak as toxic to livestock.
Is California Black Oak HOA-friendly?: California Black Oak is generally an HOA-friendly choice in the right placement, with moderate maintenance.

These answers were drafted with an AI model from this plant's data. Verify care details with a local expert.

Native range data from vouchered herbarium specimen records and regional native plant society lists. Pollinator and host plant associations compiled from GBIF, iNaturalist, and published ecological literature.

If something looks wrong

Common plant problems, and what to check first

These come up on almost any plant. Each guide lists the likely causes in the order they are worth ruling out, with one thing to check before you act on any of them, and links to the source it came from.

See all plant problem guides

Ready to grow California Black Oak? Add it to your garden in Pollinator Patch to track it and get season-by-season care guidance.

Add this plant to your garden

iPhone app Android app

Planning a bed around it? Start a free plan with this plant

Not sure where to start? Take the 2-minute yard quiz