We have olive trees by the zillions here in San Diego and have 5 or 6 of them on our property as well as citrus groves all over. The olive trees are and have been at risk for years from a blight which the state monitors in your trees with a sticky card that is collected. We have to give them medicine and care to keep them from dying. Unfortunately it is a battle but we love our trees. It is cool at night here except in summer months, which you would not expect but in the winter we wear down jackets at night in winter, especially because we eat outside at restaurants due to Covid. Olives require a lot of clean up if you don’t do olive “ birth control “ ahead of time, and the dogs eat the olives and then get stomach aches, so be careful if you have olive trees.