The carob tree has much more to give than it takes. Resistant to heat and drought, it provides plenty of shade with its spreading crown. The dark purple flowers sprout directly from the trunk and branches. The carob tree presents its masterpiece in the form of long, curved pods, whose nutritious, sweet pulp is processed in a variety of ways. In the local regions, the exotic legumes are rare. The Ceratonia siliqua, on the other hand, compensates for this deficiency by providing a home for many beneficial insects and decorating sun-drenched corners on balconies and terraces with its distinctive stature in tubs.
Table of Contents
location and substrate
Anyone who has had the opportunity to admire the carob tree in its natural environment during a trip through the Mediterranean can confirm the frugality and flexibility in terms of location requirements.
- Full sun, sunny to partially shaded position.
- From mid-May, the ornamental tree comes outside.
- Humus, sandy-gravelly soil without waterlogging.
- Use a potting soil-sand mixture in the bucket.
- The addition of grit or perlite increases permeability.
The carob tree gets along well with calcareous soils that also have a high salt content. Ceratonia siliqua only reacts sensitively to the use of pesticides in its immediate vicinity and, in the worst case, sheds all leaves without further ado.
The carob tree, as it is often called, tolerates short-term minus temperatures down to -3° Celsius. However, the sclerophyllous plant does not have real winter hardiness. Consequently, the tree is primarily cultivated as a container plant. In this context, the hobby gardener is free to purchase a ready-grown carob tree in a specialist shop or to experience first-hand how the large, shiny seeds transform into a tree that reaches a height of 10 to 20 meters in its homeland.
Cultivation from seeds is possible all year round. Since they have a very hard shell, it is advisable to roughen the kernels slightly with sandpaper before sowing or soak them in warm water for 24 hours.
- Fill small pots with seed soil or cactus substrate.
- Plant one seed at a time no more than 1 cm deep and moisten.
- Place in a semi-shady place where it does not get below 20° Celsius.
The seeds of the carob tree do not like high humidity. Accordingly, it does not make sense to place the seed pots in a mini greenhouse or to cover them with foil. No binding statement can be made about the duration of the germination period. Under favorable conditions, it sets in after just 10 days; in other cases, however, hobby gardeners report months of waiting time. It is important to note that substrate and seeds are only minimally supplied with water. If the cotyledons fight their way to the light, the seed coat should no longer be sitting on the seedling, because then it becomes critical. The young plant simply lacks the strength to shed the shell and is unlikely to develop further under the heavy load. With a pair of tweezers, a steady hand and a little luck, the experienced hobby gardener removes the hood. The danger that the seedling tears is great; it is still worth a try instead of throwing it away immediately.
- The first leaves sprout about 6 weeks after germination.
- The growing pot is then rooted and the young carob tree is ready for repotting.
- Low-nutrient, calcareous cactus or herb soil is suitable as a substrate.
When choosing the new pot, two properties should be particularly considered: It is deep enough for the taproot to develop unhindered. There is an opening in the bottom so that excess water can drain off.
- A drainage made of chippings, gravel or potsherds is laid over the water outlet.
- Ideally, the hobby gardener spreads a fleece over it so that the material does not clog.
- This is followed by a first layer of the substrate, which you mixed yourself or bought ready-made.
- The young carob tree is not planted deeper than it was in the nursery.
A pouring rim prevents unnecessary soiling from spilling water. Finally, do not forget to water the Ceratonia siliqua.
watering and fertilizing
The need for water and nutrients is low for a carob tree. The older the tree gets, the better it tolerates longer dry periods. However, the legume should not dry out completely.
- Water the carob tree only a little.
- Rainwater is just as suitable as tap water.
- Always empty any saucer.
- Start-up fertilization in spring with liquid fertilizer is sufficient.
Only with waterlogging does the Mediterranean tree not get along. If it is accidentally watered too much, it is advisable to immediately repot it in fresh, dry substrate and not to water it for the time being.
The hobby gardener is free to choose whether to cut his carob tree or not. Regular pruning keeps the wood in shape and promotes vitality. In addition, height growth is kept in check in this way.
- Prune in autumn before clearing or in spring before sprouting.
- Do not cut in direct sunlight or in sub-zero temperatures.
- Prune branches that grow out of shape.
- Remove dead, stunted or diseased branches.
- Regular pruning of the young shoots promotes branching.
The experienced hobby gardener only uses freshly sharpened cutting tools that have also been disinfected with alcohol.
Raise the carob tree to a high trunk
Thanks to its sprawling, bushy crown, the carob tree in a tub is a perfect candidate for training as a standard. The best time to start shaping is early spring.
In the first step, all branches are cut off except for a strong central shoot. No stubs – also known as coat hooks – are allowed to remain. Rather, the scissors are applied just above the branch without injuring it. After pruning, the middle shoot is cut to the desired height, which should be around 200 cm for a carob tree. This cut is made at a slight angle about 3-5 mm above one eye, because this is where the beautiful hemispherical crown of the tree should form. In the following 4 to 5 years, no pruning is done, because during this time the carob tree has the task of developing a dense system of branches from the buds of the main shoot. Shoots that grow out of the lower part of the trunk are removed immediately.
If the carob tree has spent the summer under the open sky, it is time in autumn to give it time before the first frosts.
- The winter quarters are bright, with temperatures between 8° and 12° Celsius.
- If the location is too dark, the Ceratonia siliqua sheds its leaves.
- Regular turning, by 20° at a time, prevents the shoots from getting lost.
- Water only a little and don’t give any fertilizer.
Incidentally, there is nothing wrong with placing the decorative, evergreen tree in the living room throughout the winter. The warmer the location, the higher the need for irrigation water. From mid-May, the exotic tree will be allowed back on the balcony and terrace. However, it should not be suddenly exposed to the blazing sunshine. Experienced hobby gardeners first place the tub in the semi-shade and gradually get the carob tree used to full sun.
flower and fruit
It is extremely rare in the local regions and is considered a horticultural sensation; it can still be possible for the carob tree to blossom. Especially if you cultivate it all year round in a heated, light-flooded conservatory, the legume feels so at home that it lets its rather inconspicuous flowers appear from May to September, which sprout directly from the trunk and branches. If there is a second specimen nearby, the hobby gardener can hope for a harvest of the long, dark brown legumes.
- The pods initially appear greenish in color, slowly changing to chocolate brown.
- They are 10 cm to 30 cm long, about 1 cm thick and straight or curved in shape.
- Their maturation period is 12 months on average.
Since the fruits do not fall to the ground by themselves until they are overripe, they are harvested prematurely by hitting the branches with sticks, similar to harvesting olives. Since the next generation of flowers is already on the tree at this point, it is important to be particularly careful when harvesting.
In addition to sowing, propagation by cuttings can be considered. The best time for this measure is summer, especially the months of June and July.
- choose strong shoots that are not yet completely lignified
- 4 to 8 leaves are distributed over a length of 8 to 15 cm.
- cut at a slight angle just below a bud
- Defoliate the bottom half of the cuttings to expose the nodes.
- Fill the seed pots with nutrient-poor substrate and plant the offshoots.
In the following weeks, the gardener keeps the substrate slightly moist while the cuttings root through the container in a warm, partially shaded place. When the roots begin to grow out of the water drain in the soil or sprout at the top, it’s time to plant each cutting in a new tub of fresh substrate and care for it like an adult carob tree.
diseases and pests
If the hobby gardener concentrates on species-appropriate cultivation, the carob tree rarely causes problems. On the other hand, if care is neglected, the wood will be weakened and susceptible to fungal infections and pests. Aphids in particular lurk for an opportunity to pounce on the carob tree. If the hobby gardener discovers the tiny parasites at an early stage, spraying with a soft soap solution will help. The mix consists of 15 ml of pure curd soap, 15 ml of spirit and 1 liter of water. Alternatively, the troubled plant lover uses various beneficial insects, which finally finish off the aphids. Which includes:
- lacewing larvae
- parasitic wasps
These insects are purposefully bred and are commercially available. After the work is done, they migrate again without having caused any damage to the Ceratonia siliqua.
The evergreen carob tree inspires all along the line. He calmly accepts heat, dryness, limescale or salt. From time to time, a dose of water and some liquid fertilizer in the spring are enough for the legume to decorate the balcony and terrace in the bucket in summer. Likewise, the carob tree shows pleasant flexibility with regard to its winter quarters, as long as it is light and frost-free. Equipped with an imposing, hemispherical crown by Mother Nature, the garden lover is free to prescribe a cut or not for his Mediterranean guest. From whichever perspective the Ceratonia siliqua is viewed; it is definitely an enrichment for house, yard and garden.