California Black Walnut

Juglans californica, Juglandaceae

Zones

8–10

Layer

Canopy

Lifespan

Perennial

Growth

Moderate

Guild Roles

ProducerDynamic AccumulatorShade Provider

Growing Conditions

Sun

Full Sun (preferred)Partial Shade (tolerated)

Water

Low (established)Moderate (fruiting)

Soil pH

6.5 – 8

Tolerances

Drought

Frost

Heat

Pest Resistance

Disease Resist.

Companion Plants

Chinese BayberryMyrica rubra

Nitrogen Fixation

Antagonistic Plants

Pacific CrabappleMalus fusca

Black walnuts produce juglone, a natural herbicide that is particularly harmful to apple trees and other members of the Rosaceae family.

Siberian ApricotPrunus sibirica

Black walnut allelopathic compounds are particularly harmful to stone fruits like apricots, inhibiting root development and nutrient uptake.

Andean RaspberryRubus glaucus

Juglone from black walnut is toxic to many Rubus species including raspberries

Ussurian PearPrunus ussuriensis

Juglone from black walnut severely inhibits Prunus species growth and fruit production

Desert Scrub OakQuercus turbinella

Black walnut's juglone tolerance in desert oak creates microhabitat protection while oak provides wind shelter

Chinese HackberryCeltis sinensis

Strong juglone sensitivity in Chinese hackberry limits compatibility with black walnut

Uses

Functions

Nut ProductionTimberAllelopathy For Pest Control

Edible Parts

Nuts

Common Questions

What zones does California Black Walnut grow in?

California Black Walnut grows in USDA hardiness zones 8 through 10.

What are good companion plants for California Black Walnut?

Good companions for California Black Walnut include Chinese Bayberry.

Design guilds with California Black Walnut and see companion relationships visually.

Try PatternBase free