Olive oil is made from the juice of the olive fruit. Olives are harvested around October in the Northern Hemisphere and around April and May in the Southern Hemisphere. Approximately 95% of the olive oil supply to the world still comes from the Mediterranean, and the biggest producer is Spain followed by Italy then Greece. Different regions, fruit maturity and olive plant varieties produce different flavour profiles, similarly to wine.
The olive trees are known for their hardiness, longevity and attractive appearance. They also have a long life spanand tolerate all sorts of terrain that other species could not, as well as being fire- and drought-resistant. You might see olive trees on slopes, arid areas and environments that vary with water supply.
As with any fruit crop, proper farming, fertilisation, pruning, pest and disease control and irrigation all contribute towards the quality of the olives and therefore the oil.
The production of olive oil requires care. Olive trees begin to bear fruit after around five years and can continue to bear fruit for over 100 years. Olives are green at first and turn dark in colour as they ripen in the spring months, ready for harvesting by hand or machine in winter. Ripeness has a large influence on taste and generally the later in the season the olives are picked, the sweeter the olive oil will be, while oil from early harvest fruit be more powerful and bitter.
Old groves were planted in a “low-density” manner, meaning the trees are spaced well and given the best chance to thrive. These are often harvested by traditional means with manual shakers and hand-picked. Newer olive groves are often “high density” or even “super-high density”, which means the trees are planted very closely together and designed for the harvesting machinery.