Botanical Name: Ceratonia siliqua
Common Names: Carob, St. John's Bread.
Plant Family: Caesalpiniaceae
Plant Description
Carobs are a long-lived evergreen tree native to the Mediterranean. They have dense foliage, the leaves are shiny, green, round and leathery, new growth is bronze coloured. Carob flowers in summer with male and female flowers on different trees (dioecious). Planting at least five trees will usually guarantee at least one of each sex, for pod production. Named cultivars of bisexual trees are available at some nurseries. It can take 6 - 7 years for a tree to begin to bear. The fruit is a dark brown flattened pod, 13 - 30 cm in length and about 2.5 cm wide, containing a sweet, chocolate tasting pulp and several bean-like seeds. The sugar content of the pods can be as high as 50%. Carobs grow in full sun, are drought resistant, like dry, rocky sites and tolerate any soil except heavy clay. Winter temperatures below -8°C will cause injury and can retard fruiting.
Sow When
Germinates best at 22 - 26°C soil temperature.
Temperate Areas: Spring.
Subtropical Areas: Spring.
Tropical Areas: unlikely to do well.
Planting Details
Seed Preparation: treat seed with hot water followed by a 3 day soak. Germinates in 12 - 37 days; has a low germination percentage.
Planting Depth: Seeds should be sown 2.5 - 5 cm deep in individual tree tubes. Transplant the seedling when 8 - 10 cm high, either into a larger container or into the ground before the taproot is restricted by the tree tube. Care must be taken to prevent root damage, particularly 'J' rooting, which will slow down future growth. Some growers have experimented with deeper pots created by cutting agricultural pipe into half lengthwise and then tying the pieces together with wire to create a very deep pot to protect the long taproot system. Direct sowing, of pre-germinated seeds, with treeguards, may be preferable on some sites.
Spacing: mature trees grow to a height and spread of 10 m. The suggested plant spacing is about 10 m by 7 m, which gives 110 trees/ha.
Disease Problems: particular care must be taken during propagation, as carob seed is susceptible to fungal attack by 'damping off' soil organisms. The seed raising mix should be sandy and free draining. Using a sterilised seed raising mix to prevent fungal infection may double the seedling survival rate. It is important to avoid over-watering.
Position: full Sun.
Soil Type: tolerant of wide range of soil types except heavy clay; need good drainage; pH 6.2 - 8.6
Grafting: commercial orchards should contain about 95% female plants, so grafting is necessary as seed usually produces about 70% male plants. Top grafting is most effective and is most successful when it is done to plants growing strongly.
After Planting Care: care must be taken to protect the seedling from frost and grazing animals. Watering when young is advisable.
Uses
Eating: the pods can be eaten fresh or roasted and ground into powder that is used as a caffeine-free chocolate substitute.
Fodder: a useful animal fodder; carob contains 21% protein and is eaten readily by cattle, sheep, goats and donkeys. Also useful as a bee fodder.
Windbreak: or privacy screen.
Industrial: the seeds are 35% gum which is used to make adhesive.
Shade: often used as street trees, also useful to shade stock in paddocks.
