Olive trees are one of the world’s oldest cultivated trees, dating back to ancient Greece. They’re tough, drought hardy and famous for their delicious, plump fruit, which can be picked, pickled and enjoyed – no wonder these beauties are still popular today. But if fruit isn’t what you’re after, olive trees (Olea europaea) are also evergreen, have stunning silver foliage and clip well, making them ideal for topiary, hedges or espalier.
• Climate Olive trees are native to the Mediterranean, so they thrive in a climate where the summer is long, hot and dry and the winter is cool (they’re quite frost tolerant). Not suited to the tropics, they will grow well in temperate climates and even along coastal areas.
• Aspect Plant in full sun where the tree will receive at least six hours of direct sunlight. Preferably give it a position out of strong winds or stake well.
• Soil These trees can survive on poor, low-nutrient soils, providing they are well-drained. However, they will produce better fruit if planted in well-drained, fertile soil. If you’re growing in pots, use a top-quality potting mix.
• Fertiliser Feed in early spring and late summer with a well-balanced fertiliser, such as Yates Dynamic Lifter Advanced For Fruit & Citrus or Osmocote Plus Organics Fruit & Citrus, which feeds the plant and enriches the soil, too.
• Watering Water new trees regularly until they’re well established. Mature trees are very drought tolerant but will produce better fruit if watered well.
• Pruning To encourage growth, prune out suckers and low branches during winter, and remove the tips of stems that have grown too long.
• Pests and diseases Keep an eye out for olive lace bugs. These are native Australian critters that suck sap from the underside of the leaves – they can completely defoliate the tree and eventually kill it. If seen, thoroughly spray the underside of the leaves with a product such as Eco-oil or pyrethrum. Peacock spot, a widespread fungal disease, can also affect the leaves and strip the tree of its foliage. It causes sooty blotches to form on the leaves in winter, which develop into greenish-black circular spots. To control the disease, infected trees should be thoroughly sprayed in late autumn with a copper fungicide such as Yates Fungus Fighter Copper Fungicide. If the problem is severe, spray again in early winter.
• Harvesting Once the tree is four or five years old, it will start to bear fruit. Harvesting generally takes place from mid-autumn to early winter. For green olives, pick your fruit when it turns from dark green to light green, or you can wait for them to turn black, but still firm, for black olives. They can be picked by hand or, for the more serious pickers, spread a sheet or tarpaulin on the ground underneath the tree, then shake the tree vigorously to free the fruit.
Top 5 olive trees
Check out these well-known olive cultivars – their fruit can be pickled or pressed into oil.
‘Kalamata’ produces juicy, sweet olives that are harvested once they turn black. Recognisable by their unique torpedo shape, they are ideal for cooking or eating on their own. This variety is self-fertile, but fruiting may improve if cross-pollinated with Frantoio. Height: 8m
‘Picual’ is a medium-sized tree originating from Spain. It bears fruit early in the season that’s best picked when ripe. This variety is self-fertile but may benefit from cross-pollination with Arbequina. Height: 6m
‘Frantoio’ is well-known for it olives, which are used to make fruity, aromatic oil. When pickled, these olives have a pleasant nutty flavour. Frantoio is a self-fertile variety that consistently produces heavy yields. Height: 8m
‘Manzanillo’ is one of Spain’s finest varieties. It’s considered the world’s best dual-purpose cultivar as its olives can be pickled when they’re green or black, and are also used to produce oil that is exported internationally. This variety is self-fertile, but may benefit from cross-pollination with Frantoio and Arbequina. Height: 5m
‘Arbequina’ bears olives that are traditionally used for oil production, but they can also be pickled green or black. This variety is self-fertile and fruits early in the season. Height: 4-5m