Underneath the spreading carob tree

By Clive Goodacre

PlantScape Garden Centre,

Almadena

THE CAROB (Ceratonia siliqua) must be one of the most underused landscaping trees in Portugal, despite being part of the natural surroundings for thousands of years. It grows almost everywhere, often unkempt in the roughest and poorest soil, which probably accounts for why people planning a new garden seldom specify this outstanding tree. But it deserves a closer look. Evergreen foliage, drooping curved branches, reddish autumn flowers and gnarled shiny brown seedpods make the carob unique. Known as alfarrobeira in Portuguese, surprisingly few expats can identify the carob tree.

Increasingly, development is eating up old carob orchards, so if you are lucky enough to have a mature specimen growing on your land, treat it with respect as carobs have a long history. The name Ceratonia is derived from the Greek word keration, meaning horn, which refers to the shape of the carob tree’s pods that are ground into flour and used as a chocolate substitute. Pods can be eaten straight off the tree. They can be green or brown, tasting sweet and a bit like chocolate. Singers are reputed to chew them to strengthen the vocal cords. Carob seeds were originally used to weigh gemstones because of their uniformity in size and weight. Diamonds are measured in carats, which weigh 200 milligrams – roughly the same as an average carob seed.

When choosing carobs, it is better to go for grafted ones or mature specimens, as trees grown from seed can take around 15 years before producing fruit. If left to grow naturally, a carob has long sprawling branches reaching the ground, but it can easily be pruned into a fine canopy, making it a perfect shade tree.

Old carobs can be moved with mechanical assistance in a similar way to old olives: firstly, cut them back to a main trunk with short limbs and then dig them up, taking care to cut broken roots cleanly. Autumn and late winter are best times for moving them. Although noted for their drought resistance and ability to grow in poor soil, carobs respond well to fertilisers and regular watering provided drainage is good.

Palm frond screening

Sometimes things get over-engineered in the garden when simplest is best. This was brought home recently when I needed to provide temporary wind and visual screening on a section of chain link fencing until hedging became established. Green netting seemed the cheapest and easiest option, until I remembered seeing Phoenix canariensis palm fronds used for this purpose on an old farm. They simply had their ends trimmed square and were held vertically against the fence by means of plastic ties along the top wire. They may look like something from Robinson Crusoe, but are in plentiful supply, add bucolic charm and will last through the winter.

Several garden centre customers have asked why their Bermuda lawns are looking yellow and whether fertiliser would green them up. Their appearance is, of course, quite natural in the winter, as Bermuda grass does not like cold weather in any shape or form and as well as turning yellowish will also virtually stop growing. But it may be a combination of causes, as Bermuda does not like overwatering or badly drained soil, so turning off the irrigation may help things.

A different type of water problem surfaced the other day, when a customer asked why the citrus trees we supplied her had hardly grown after a year and were looking pathetic to say the least. A site visit established they were planted in rich agricultural soil fed with water from an old well in the middle of the orchard. She had been told by local farmers that the well was ‘bad’, by which she assumed it ran out in summer. However, it was bad because, on testing the water, it proved to be salty and high in chlorates, which was slowly killing the trees. Interestingly, some wild olives, pistachio and carobs were thriving alongside the citrus trees.

• If you have any gardening questions, contact Clive by email on [email protected]