The olive tree, known scientifically as Olea europaea, is an ancient species domesticated by humans roughly 6,000 to 8,000 years ago in the Eastern Mediterranean. This evergreen tree is a foundational element of global agriculture, providing fruit and oil that are staples worldwide. The olive holds profound cultural significance, often serving as an enduring symbol of peace, longevity, and abundance across many civilizations. Its distinctive gnarled trunk and silvery-green foliage testify to its resilience. Some specimens have survived for thousands of years, highlighting the tree’s adaptability.
The Native and Traditional Heartlands
The vast majority of the world’s olives are still cultivated within the Mediterranean Basin, the area where the species first evolved. This region, spanning Southern Europe, North Africa, and the Levant, provides ideal conditions for large-scale production. Spain is the global leader, often accounting for nearly half of the world’s olive oil supply.
Spanish production is heavily concentrated in the southern region of Andalusia, particularly in provinces like Jaén and Córdoba. Italy and Greece follow as major traditional producers. Italy’s output centers largely in Puglia and Calabria, while in Greece, the Peloponnese peninsula and Crete are primary areas, often producing high-quality oil from the Koroneiki variety.
The traditional heartland also extends across the southern and eastern shores, including major producers like Turkey, Tunisia, and Morocco. These countries benefit from the consistent climate and have millennia of cultivation history. The scale of production and deep-rooted agricultural practices in these areas define the global olive market.
Essential Climate and Soil Requirements
The geographical distribution of olive cultivation is determined by a specific set of climatic and soil conditions that mimic the Mediterranean environment. The trees require long, hot, and dry summers, which they are adapted to withstand through drought tolerance. This season is necessary for the fruit to mature properly and achieve a high oil content.
A period of cold during the winter is necessary for the tree’s reproductive cycle. Olive trees must accumulate “chilling hours”—typically 200 to 600 hours between 2°C and 10°C (35°F and 50°F)—to ensure sufficient flower bud differentiation. Without this cold period, the tree will not flower or set an adequate amount of fruit.
The tree is sensitive to prolonged hard freezes, which limits its northern and high-altitude spread. Temperatures dropping below -5°C (23°F) can damage fruiting shoots, and younger trees can be killed below -10°C (14°F). Cultivation is thus restricted to areas with reliably mild winters that satisfy the chilling requirement without destructive frost.
Regarding soil, the olive tree is highly tolerant of poor, rocky, and calcareous conditions. These conditions often discourage excessive vegetative growth and promote better fruit quality. The absolute requirement is excellent drainage, as the trees are intolerant of waterlogging. Aerated, shallow soils on hillsides or slopes are often preferred, as sites where water stands are unsuitable.
Emerging Global Cultivation Regions
Outside of the Mediterranean, olive cultivation has expanded significantly in regions that share similar climate patterns, often leveraging modern agricultural technology. The New World and Southern Hemisphere have become important secondary production areas. In the United States, production is heavily concentrated in California, accounting for over 95% of domestic output, mainly in the Central Valley.
South America has seen major expansion, with Argentina holding substantial hectarage, followed closely by Chile. These arid zones often rely on intensive farming methods and supplemental irrigation to sustain high-density groves. This modern approach contrasts with the rainfed, traditional groves common in the Old World.
Australia and South Africa are also established non-traditional producers, having successfully introduced Mediterranean varieties like ‘Arbequina’ and ‘Picual’. Australian groves require sophisticated water management systems due to the naturally low rainfall in suitable microclimates.