The Spanish introduced Olea europaea to the Mediterranean basin in 8000 B.C. The longevity of these noble trees is legendary at thousands of years. Olive oil production dates back to the Bronze age. With a maximum height of 15 metres, olive trees have got hard, dense wood and grow very slowly and irregularly, where the lack of rings makes it difficult to age them precisely.
There are two lovely Provençal sayings, « à 100 ans, un olivier est un jeune homme » and « autant le figuier que l’olivier ne meurent pas sans héritier » which mean a 100-year-old olive tree is a young man and the lovely expression, like fig trees, olive trees don’t die without an heir. As an olive tree ages, it produces new « souquets » or shoots from the stump. So the new tree that grows isn’t really a new tree, but a new version of itself, a new expression of the same genotype.
Olive trees aren’t fragile but can be subject to several diseases caused by fungi and insects. The Provence fly makes a little hole in the fruit of the olive to lay her eggs, which then hatch and leave the olives relatively intact. In 2014 an invasive little fly appeared that caused catastrophic consequences for the crop. Their plentiful offspring have a disastrous effect on the fruit resulting in them falling off the tree and rendering them useless. Interesting to note is that this little beast is too small to pierce the skin of the olive, so they need to use the same hole that the local flies made. The only effective solution against the flies are pheromone traps.
Despite the longevity, it is possible to kill an olive tree. The harsh frost of 1956 springs to mind where two thirds of the olive trees in Provence were decimated. Although the frost may not be solely responsible; one cannot ignore that many trees were sold for firewood during that period. Olive trees also struggle to survive if there is too much water in the soil, or no water at all, or if the tree needs to compete too much with its neighbours for essential nutrients.
Pruning is done at the beginning of spring, in March or April, after the frosts and can be done in two ways. Ornamental pruning is done for aesthetic results, while olive production requires a harder pruning to encourage better fruit growth. Farmers in Provence say that an olive tree has been pruned well when a swallow can fly through its branches unhindered. Olive trees can be transplanted, but it’s advisable to maintain the orientation of the foliage to the sun (tip: moss growing on the trunk shows a Northern exposure) and give it a good watering so it can develop its root system again.
The historical symbolism of olive trees is very strong and varied: they represent strength and victory, wisdom and loyalty, immortality and hope, wealth and abundance.
Blog post written in conjunction with my brother Damien Gentaud, who is a landscape gardener in Cotignac. He is passionate about nature and his work, and loves sharing his knowledge.