Olives, specifically, the European Olive (Olea europaea L.), are grown commercially in California for table black olives and table oil. Virtually all of this production is in the Central Valley of California. Within the north Sacramento Valley, this acreage is located in Butte, Glenn and Tehama counties. Within the south San Joaquin Valley, this acreage is located in Fresno, Kern, Madera and Tulare counties. The Mediterranean climate of these areas, characterized by hot, dry summers, cool winters, and dry springs when the trees are in bloom, is suited to olive production. Well-drained soils are preferred. (Olive Production Manual, 2005. p. 5)
In 2010 the total crop (for oil and table) from the 33,000 acres harvested in the state had a market value of $113,360,000. (California Agricultural Statistics 2010 Crop Year). In 2011, an estimated 30,000 acres was harvested for olive oil, representing doubling of oil production since 2008 (California Olive Oil Council, 2011).
Olive trees are evergreen, with small, leathery leaves, and gnarled branches. They are long-lived, and producing fruit by year 4 and reaching maturity by year 15. (Fabbri,, et al. 1004) the waxy cuticle and show transpiration rate of the leaves offer drought-resistance. One monthly deep watering is usually adequate. Olive flowers are small, and grow on a long stem arising from the leaf axils. The olive produces two kinds of flowers: a perfect flower containing both male and female parts, and a staminate flower with stamens only. (Olive, California Rare Fruit Growers, 1997). Research indicates that flower development begins in November, but full bloom does not occur until May. The flowers are largely wind pollinated with most cultivars being self-pollinating, although fruit set is usually improved by cross pollination with other cultivars, thus Sevillanos are often planted near Manzanillo trees. (G.C. Martin and G.S. Sibbett, Botany of the Olive p. 15-17 in Olive Production Manual, 2005).