There are two basic types of grapes, American and European. Grapes can grow in almost every type of climate
Grapes should be plump and firmly sttached to the stem. Full color implies better flavor. Green grapes should be a translucent yellow-green rather than a grass gree. Red grapes should be crimson. Blue grapes should be almost black. Avoid wrinkled or sticky grapes.
Refrigerate grapes in a vented palstic bag for up to a week.