In the ongoing pursuit of new cash crops for Hawaii, some farmers are planting Mediterranean olive trees as a possibility. Several farms on Maui have planted hundreds of plants with the first full production year approaching. Though most varieties require a seasonal chill to flower and fruit, several cultivars hold production promise in the tropics when grown at upper elevations
Aside from their production ability in Hawaii, olive trees can be planted as lovely specimen plants requiring so little care that they can be used in a xeriscape landscape. They can tolerate a variety of soil types as well as drought, hot sun and mild salt spray. Despite their shallow roots, the trees can withstand moderate wind. Olives are unlikely to fruit at lower elevations, but if they do produce fruit, you need to be prepared to harvest them. Though the tree can serve as an attractive ornamental, dropping fruit can be messy in small garden areas.
The fruit can be used in many ways depending on harvest time and processing choices. The martini olive needs to be picked early in the season and subjected to brining. Midseason harvests produce great olive oil and black olives harvested later can make wonderful salad additions or tapenades.
The European olive, Olea europaea, has become invasive in several places including Australia. It is currently listed in Hawaii’s Most Invasive Horticultural Plants. Since the best way to propagate olives is by cuttings, care with discarding cuttings can reduce spreading. Limiting access to the trees by large birds or other animals that might eat the fruit and spread the seeds into native forest areas is also needed to keep olives from becoming invasive.
Olives are native to the Mediterranean region and western Asia. A native Hawaiian olive, Nestegis sandwicensis, (olopu in Hawaiian) is in the same Oleaceae family, but it does not produce edible fruit and is not widely grown. Other species in this family that are grown as ornamentals include privet, jasmine and pikake.The olive tree — Hawaii’s Most Invasive Horticultural Plant,