Ceratonia siliqua
Common Name: St. John's bread 
Type: Tree
Family: Fabaceae
Native Range: Mediterranean, Arabia, Somalia
Zone: 9 to 10
Height: 30.00 to 50.00 feet
Spread: 30.00 to 50.00 feet
Bloom Time: September to November
Sun: Full sun
Water: Dry
Maintenance: Low
Suggested Use: Shade Tree, Street Tree
Flower: Insignificant
Leaf: Evergreen
Fruit: Showy, Edible
Tolerate: Drought, Dry Soil, Shallow-Rocky Soil, Air Pollution


Best grown in dry, well-draining, sandy loams in full sun. Tolerant of a wide range of soil types including poor, rocky soils as long as they are well-draining. Highly tolerant of drought but infrequent, deep waterings will improve fruit production. Intolerant of waterlogged soils. Tolerant of salt spray, air pollution, and urban conditions. Hardy in Zones 9-10. Prefers mild climates with cool winters and warm to hot summers. New spring growth is frost tender. Propagate through seed.

Noteworthy Characteristics

Ceratonia siliqua, commonly called the carob, is a small to medium sized, slow growing, evergreen tree originating in the eastern Mediterranean and the Arabian Peninsula and now widely cultivated throughout the Mediterranean and other warm temperate regions including coastal South Africa, southern Australia, western North America and Chile. Mature trees will reach 30-50' tall with a dense, rounded canopy of similar width and a stout trunk and thick branches. The compound leaves can reach 4-8" long and have 4-10, generally opposite pairs of ovate to elliptic leaflets. The leaflets can reach 1-2.75" long and are dark green with a leathery texture. The small and apetalous (lacking petals) flowers are held on 2-6" long, catkin-like racemes that emerge from the twigs and sometimes the trunk in autumn. Bloom time is greatly affected by local climate. This species is typically dioecious, with female and male flowers found on different individuals, but trees can also occasionally have perfect flowers or inflorescences with both male and female flowers. The seed pods mature from smooth and green to wrinkled and dark brown. The 4-10" long pods can be straight or curved and are indehiscent, meaning they do not split open at maturity.

Genus name comes from the Greek word keratonia the name of the carob, from the Greek word keras meaning horn for the pods.

The specific epithet siliqua comes from the Latin meaning "pod", in reference to the seed pods produced by this species.

The common name St. John's bread refers to the biblical figure John the Baptist who is said to have eaten the pods of this plant. The common name carob originated from the Assyrian or Aramaic (and related Hebrew) words for this plant that were then adopted by Arabic and finally French.


The carob moth and wood leopard moth are most significant pests of this plant. Scale insects and feeding damage from rats, rabbits, pocket gophers, ground squirrels, and deer are also problematic. Young plants are more susceptible to browsing damage than mature trees. Surface roots can be problematic if this tree is grown too close to sidewalks or driveways. The seedpods can be messy and require cleanup. This plant has escaped cultivation in California and has the potential to be quite aggressive, spreading through seed and resprouting from cut stems in disturbed habitats.


Shade tree and street tree. Suitable for xeriscaping and seaside plantings. The pods are high in sugar and once seeded can be processed into animal feed, or roasted and milled into a powder for use as a cacao substitute and flavoring in baked goods, sweets, and beverages. A gum extracted from the seeds is used as a thickener, stabilizer, and binder in a wide variety of processed foods, cosmetics, pharmaceuticals, and chemical products. It is often listed on ingredient labels as carob bean gum or locust bean gum.