Grapes were first cultivated in the Near East 6,000 to 8,000 years ago. There are over 60 varieties of grapes that are cultivated for wine making and over 50 varieties are in current production as table grapes. Over 200 years ago, Franciscan monks brought grapes to California for the purpose of making sacramental wine.
Grapes enjoy temperate weather and grow particularly well in regions where the climate is similar to the Mediterranean. California produces 97 percent of all the European varieties grown commercially in the United States. California is third in the world in table grape production, behind Italy and Chile. The two types of grape species grown in the United States are the Native American, and the European. There are an estimated ten thousand varieties of the European species, but only a dozen or so are imported as table grapes. Native American grapes are sometimes referred to as "slip skin grapes" because their skins easily separate from the flesh. Another common characteristic of this group is that their seeds remain tightly imbedded in the flesh. Concord grapes are the most familiar Native American variety.
Grapes are typically harvested when fully ripe, so they should be ready to eat when you buy them. Use color as a guide to the sweetness of the fruit. Green grapes should have a slight yellow cast with a touch of amber when fully ripe, not an opaque grassy green color. Red grapes should be a deep crimson, not a milky or pale red. Blue or black grapes should be darkly hued, almost black, not pale or tinged with green. Grapes showing signs of decay, shriveling, stickiness, brown spots or dry brittle stems should be avoided. Grapes should be plump, so avoid any that have lots of under-developed, very green fruit. You can always judge the freshness of grapes by the stem. The greener the stem, the fresher the grapes. Grapes should always be firmly attached to their stems.