Olives were first grown in the Mediterranean around 2,500 B.C., according to the California Rare Fruit Growers Inc. Today, olive trees are grown where the climate is most favorable. Olive trees need the proper climate to produce fruit, as too low of a temperature will damage or kill them.
California and Arizona are the leading olive producers in the U.S. because of their warm growing seasons. Olive trees can't grow in climates where temperatures frequently dip to around and below 15 degrees Fahrenheit for long periods of time, such as Pennsylvania during the winter.
Although olive trees cannot grow if temperatures are unfavorable, they require a cool-down period of about 50 degrees Fahrenheit that enables them to prepare for flowering in the spring.
In Pennsylvania, olive trees can be grown in greenhouses, where climates can be controlled during the cold, winter months.