The latter two are large-fruited table olives that may yield only 12 to 15 gallons of oil per ton of fruit, while the Mission and Italian varieties may produce 40 to 50 gallons per ton. There are many production costs necessary to achieve the economic yields of two to six tons per acre yearly. Olives will survive on very poor sites with shallow soils but will grow very slowly and yield poorly. Deep soils tend to produce excessively vigorous trees, also with lower yields. The ideal site for olive oil production is a clay loam soil with good internal and surface drainage.
Irrigation is necessary to produce heavy crops and avoid alternate bearing.
Regular pruning should be employed to reduce alternate bearing of trees, to encourage production throughout the tree canopy, and to produce sufficient shoot growth for the next year's flowering and fruiting. Olives bear on the previous year's shoot growth, which is shunted while in competition with an excessively heavy fruit load. Harvesting is one of the most expensive operations in an olive orchard. Many growers try to shake, rake, or beat the olives off the trees onto tarps or nets to reduce harvest costs. To produce the valued extra-virgin oils, high quality fruit is crushed in either stone grinders or metal hammer mills.