Olive trees produce an abundance of small, white, perfumed flowers in summer. Flowers can be damaged easily by strong winds and heavy rain. Good rainfall or watering in the winter is essential for a heavy crop. A healthy olive will flower and set fruit in Spring. Generally, fruit matures in Autumn.

The black or green olives that are sold today are not produced by different trees. At first the olive’s fruits are green but become satiny and dark as they ripen. After maturity they cling to the tree for several weeks before falling to the ground.

Cultivar is a plant variety produced by cultivation.

Most olive trees are selfpollinating and do not require crosspollination.

Australia is fortunate to have many of the world’s most valuable olive cultivars already on its shores. In many instances, cultivars have been brought by people migrating from Mediterranean regions to Australia. The variety may have been a particular favourite in their homeland, so they decided to bring it to the new country with them.

On arriving in Australia, many of the cultivars were given new names. New settlers may have wanted to name the trees after their home-town or maybe a loved one. This factor has caused considerable confusion as to the true identity of some cultivars.

It is believed the only biological method able to 100% guarantee an olive’s true cultivar origin is ‘reading’ the pattern of grooves on the seed of the fruit. Each cultivar has its own ‘fingerprint’ on the seed but there are very few people in the world skilled in seed identification. These days, leaf shape, size and colour; fruit and seed size; flesh texture and oil content are more likely to be used for cultivar identification.

Until recently, it was generally believed that commercial olive groves would only crop in areas south of around Coffs Harbour. However, commerical cultivation over the past few decades has proven that many areas north of this latitude have perfect climates for domestic and commercial olive production. Indeed, there are many regions in Queensland, due to their altitude or other geographic aspect, that are very suitable for commercial olive orchards. Olive plantations are becoming increasingly popular on the Darling Downs and olives can be successfully grown in gardens in and around Brisbane, providing they have a sunny, well-drained position.

It is fortunate that strict quarantine standards in Australia mean that olives are relatively disease-free. Most olive trees are self-pollinating and do not require cross-pollination. However, when grown commercially, pollinators are recommended to increase the yields of certain cultivars. In general, research suggests that commercial growers should plant at least three different olive varieties, in close proximity, to ensure some crosspollination.

Olives prefer cold winters and long, hot summers to produce mature, goodsized fruits, and they grow well in gardens in and around Brisbane. The trees are fairly shallow-rooted but because of their narrow leaf surface they are drought tolerant. Olives require welldrained soils.

Fertilise olives by spreading citrus fertiliser evenly around the tree each winter before the end of August. Olives benefit from mulching.

Olives produce most of their fruit on shoots arising from the previous year’s wood. They need little pruning other than to encourage outward growth. Prune to control vigorous growths and to remove any crossed branches.

Although you can expect to wait about five years before fruiting, olive trees can continue bearing fruit for hundreds of years. Always handle the fruit carefully, as bruised fruit does not pickle well.

Traditional style harvesting and pickling

Be warned – these olives are so good you could end up with more friends than olives! Tell them to plant a tree or two for themselves.

The commercial pickling process usually involves a combination of ingredients like caustic soda, food acids and salt.

Although there are many different ways to prepare and process olives, one of the simplest methods is to follow this traditional Greek recipe that uses only salt.

Olives can be pickled when green or black. A black olive is simply a ripe olive. In general, green olives are pickled and black olives are used for oil.

The appropriate time to pick green olives for pickling is when some of the olives begin to change colour towards black. When your olives are ready to pick place cloth sheets on the ground under the tree and strip the tree of fruit using your hands or a pronged rake. After collecting the fruit, remove odd stems and leaves and rinse olives in clean water in a bucket.

Bruising, pricking or cutting will allow the water and salt to penetrate the fruit.

Place the olives on a clean stone surface or cutting board and bruise them with another stone or wooden hammer. Alternatively, prick several times with a fork, or make three slits in the skin of each olive with a small serrated knife while turning the fruit between the thumb and index finger. This helps preserve the fruit by allowing the water and salt to penetrate drawing out the bitterness.