California Buckeye (Californica)

The California Buckeye (Californica) is generally described as a perennial tree or shrub. This is native to the U.S. (United States) has its most active growth period in the spring and summer . The greatest bloom is usually observed in the summer, with fruit and seed production starting in the summer and continuing until fall. Leaves are not retained year to year. The California Buckeye (Californica) has a long life span relative to most other plant species and a moderate growth rate. At maturity, the typical California Buckeye (Californica) will reach up to 40 feet high, with a maximum height at 20 years of 30 feet.

The California Buckeye (Californica) is usually not commercially available except under contract. It can be propagated by bare root, container, seed. It has a slow ability to spread through seed production and the seedlings have high vigor. Note that cold stratification is not required for seed germination and the plant cannot survive exposure to temperatures below 2°F. has high tolerance to drought and restricted water conditions.

Uses of : Landscaping, Medicinal, Culinary, etc.

Ethnobotanic: This tree had multiple cultural uses among California Indian tribes. Many indigenous groups utilized buckeye seeds for food, often when other plant food sources were scarce. These tribes included the Costanoan, Salinan, Kitanemuk, Serrano, Wappo, Sierra Miwok, Coast Miwok, Chumash, Kawaiisu, Northern Maidu among others. The Pomo ate the seeds even when other important food plants were plentiful. The seeds are poisonous to humans in the raw state. Thus, the nuts were cracked open with a rock, the shells removed, the seeds pounded into flour, and their toxic saponins removed in a lengthy leaching process. The meal was subsequently cooked and eaten. There are many different methods for processing and cooking buckeye seeds for food, depending upon the tribe. The seeds have medicinal properties and were cut into pieces, mixed with water, and made into suppositories for hemorrhoids by the Costanoan and Kawaiisu. The Pomo cut bark from the base of the tree and made a poultice, which was laid on a snakebite. Young buckeye shoots were sometimes used as spindles or twirling sticks in fire-making kits of the Sierra Miwok, Northern Maidu, Wappo, Yahi and other tribes. Many tribes mashed buckeye nuts and poured the contents into quiet pools to stupefy or kill fish.

Wildlife: Do not plant buckeyes near apiaries as the flowers are poisonous to honey bees. No wildlife eat buckeye seeds except squirrels, such as the California ground squirrel (Citellus beecheyi).

General Characteristics

General: Buckeye Family (Hippocastanaceae). This native, deciduous shrub or tree reaches 12 m in height with a broad, rounded crown. The palmately compound leaves occur in leaflets of 5 to 7 and each leaflet is oblong-lanceolate and finely serrate. The inflorescence has many showy flowers in a panicle-like arrangement and it is erect, 1-2 dm. in length. Each individual flower has 4-5 petals and these are white to pale rose with 5-7 exserted stamens. The fruit is pear-shaped and smooth. The large, shiny light-brown seeds are 2-5 cm.

Required Growing Conditions

For current distribution, please consult the Plant Profile page for this species on the PLANTS Web site.

Cultivation and Care

Adaptation: The California buckeye is one of the first shrubs to leaf out in spring and one of the earliest to shed its leaves in mid-summer. It is found on dry slopes, canyons and the borders of streams in many plant communities below 1700 m. in northwestern and central western California, Cascade Range, Sierra Nevada foothills, Tehachapi Mountains, Great Central Valley, and southwestern Mohave Desert.

General: Harvest the large seeds from the tree or shrub about November. Plant them in the ground immediately--half buried in an area of full sun or light shade. There is a light spot on the seed, which is the growing point when being formed. The radicle will sprout from this area so make sure that this spot is covered with soil. Plant the seeds in a well-drained soil. Water the soil immediately after planting, and if there is not enough rain during the rainy season, supplement it with hand watering. The plants will also need some summer watering the first year so a good rule to follow is to keep the soil damp. The tree is a fast grower and can achieve as much as ten inches in height in one year. After buckeye seeds have been in the ground one full year, they should become established, and will not need continual care.

General Upkeep and Control

When the shrub is mature dead and dying branches can be lightly pruned if necessary.

Plant Basics
Growth Rate Moderate
General Type Tree, Shrub
Growth Period Spring, Summer
Growth Duration Perennial
Lifespan Long
Plant Nativity Native to U.S.
Commercial Availability Contracting Only
Physical Characteristics
Bloom Period Summer
Displays Fall Colors Yes
Shape/Growth Form Single Stem
Drought Tolerance High
Shade Tolerance Intolerant
Height When Mature 40
Vegetative Spread None
Flower Color White
Flower Conspicuousness No
Fruit/Seed Abundance Medium
Fruit/Seed Seasonality Summer Fall
Seed Spread Rate Slow
Gardening Characteristics
Propagations (Ways to Grow) Bare Root, Container, Seed
Moisture Requirements Medium
Cold Stratification Required No
Minimum Temperature 2
Soil Depth for Roots 36
Toxic to Nearby Plants No
Toxic to Livestock No
After-Harvest Resprout Ability Yes
Responds to Coppicing No
Growth Requirements
pH Range 5.5–7.5 pH
Precipitation Range 14–14 inches/yr
Planting Density 300–700 indiv./acre
Soil Textures Coarse
Soil Depth for Roots 36
Minimum Frost-Free Days 175 day(s)
Salinity Tolerance None
CaCO3 Tolerance Low
Sustainability & Use
Leaf Retention No
Palatability Low
Fire Resistant No
Causes Livestock Bloating None

Source: USDA, NRCS, PLANTS Database,
National Plant Data Center, Baton Rouge, LA 70874-4490 USA