In Season: Popular for centuries in Spain and Italy, blood oranges are now being cultivated in the United States. Look for blood oranges in specialty supermarkets from November through May. What to Look For: Blood oranges are somewhat smaller than navel oranges, and often have pitted skin mottled with hints of red; the interior flesh is deep crimson. The flavor is sweeter and less tart than other oranges, and may have hints of raspberry or a slightly bitter edge. Choose firm, plump oranges that are heavy for their size. How to Store: Blood oranges will keep at room temperature for several days, kept in a bowl or basket where air can circulate freely. To store oranges for up to two weeks, put them in an airtight bag or container and place them in the produce drawer of the refrigerator.