Answer: If you're making green olives, you pick the fruit when it's green. Otherwise, the fruit is allowed to ripen until it is a deep green (almost black). When the fruits begin to drop from the tree, most will be ripe and ready for harvesting. They bruise easily and can develop mold if not handled carefully. For curing the olives, you'll want to get a copy of University of California Agricultural Sciences's Publication Leaflet 21131. It covers all the techniques in great detail. Contact your local Cooperative Extension office or visit the University of California Agricultural Sciences website.
Best wishes with your project!
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