The Versatile Olive Tree
By Virginia Hayes
A handful of trees are so ubiquitous in the California landscape that it seems as if they have always been here. Eucalyptuses and palms are two such groups and one, Schinus molle, even goes by the common name California pepper tree, although its home is in the Andes Mountains in Perú. One other adaptable and common tree from Europe (probably the Middle East) is the olive (Olea europea). The olive was domesticated thousands of years ago and its use spread throughout the warmer areas of the European continent. Useful for its cured fruits, the oil they produce, as well as fine-grained wood, olive trees were considered essential to every homestead. They were first brought to California by the Spaniards who planted them at their missions and further introductions followed throughout the 1800s to the present. Individual trees may live to be hundreds of years old, with many documented at 600 years or more. Those on the Mount of Olives in Jerusalem are reputed to be 2,000 years old and the oldest living tree, growing in Crete, is said to be 5,000 years old.
In recent years, olives have become somewhat of an icon for the Mediterranean lifestyle and landscape. Mature trees have gnarled trunks, spreading branches, and a full crown of glossy green leaves that have a silvery underside giving the whole tree a gray-green aspect. They top out at 25 or 30 feet in height and can have an equal spread. Young trees get their height fairly quickly, and then slowly attain their character.
They can be trained as a single-trunked specimen or suckers can be selected to produce a multi-stemmed plant. Plants should be sited carefully as most varieties produce fruit that drops and can stain patios or sidewalks. If planted over a sidewalk, foot traffic can also pick up the juice and bring it inside to ruin rugs or carpets. However, several selections profess to be fruitless. These varieties may bear tiny fruits that pose less of a problem or flower sparsely and set very small crops. Look for ‘Bonita,’ ‘Majestic Beauty,’ ‘Swan Hill,’ or ‘Wilsoni.’ One other selection, ‘Little Ollie,’ also bears almost no fruit and is much smaller than other olives, forming a dense shrub up to 12 feet in height. These non-flowering varieties are also desirable if you suffer from allergies. Olive pollen is a common irritant for many people.
It is possible to use a plant growth regulator to prevent fruit formation. These are available under a number of names such as Florel and Fruit Stop and must be sprayed on during flowering to be effective. As you can imagine, this method is difficult and expensive with large trees. Selective pruning of the branches formed in the previous year can eliminate much of the flowering potential. Pruning can also be done to develop a more handsome structure.
Tough and versatile, the trees prefer rich soil, but will tolerate almost any situation. They are drought tolerant once established and thrive in the hottest inland areas as well as at the coast. Olives require little, if any, fertilizer and withstand freezing temperatures to about 15 degrees Fahrenheit. If you are planting for fruit production, trees will begin to bear at about six years of age.
Olives are one of California’s hottest agricultural crops these days. There are nearly 40,000 acres of olive trees in production and more acres are being planted each year. Most of the fruit will be processed for table olives, but the oil market is strong and a growing number of orchards are devoted to these types. Although the trees continue to produce for many years — there are olive orchards in California with trees that have been in production for more than 100 years — the usual lifetime is about 50 years. As newer varieties of olives are developed, farmers may also sacrifice old trees in order to replant with a more desirable selection. Unlike some other fruits, though, there is a second market for these trees after they are removed. Olive trees transplant quite easily, so it is not uncommon to see new housing developments with mature olives gracing their streets or gardens. Their contorted trunks and large stature lend their character to the landscape immediately. There are tree brokers that specialize in procuring and planting them if you desire to get a mature look without the decades-long wait.
Even if you don’t want to try your hand at preserving olives or form a local co-op to press your own olive oil, you are sure to love the look of an olive tree in your own garden.
Virginia Hayes, curator of Ganna Walska Lotusland, will answer your gardening questions. Address them to Gardens, The Independent, 122 W. Figueroa St., S.B., CA 93101. Send email to email@example.com.