Stone says the best place to store grapes is in the perforated plastic bag you buy them in (or in a paper bag) in the refrigerator. But, he notes, if you're buying lower quality grapes (you'll know if they're wrinkled, brownish or white where they connect to the stem), there's only so much you can do to make them last longer than a week.
This article explains that grapes from Chile could be months old by the time consumers get them, despite growers' best efforts to store the fruit well. Sweet, crisp Mexican grapes land in supermarkets much more quickly after harvest—sometimes within a week.
