Rutabagas are root vegetables that resemble a large turnip and have sweet, pale yellow-orange flesh and tan, green, or purple skin. They are also known as swedes or Swedish turnips. The sweetest rutabagas are no more than 3 or 4 inches (7.5 or 10 cm) in diameter and should be firm and heavy for their size. Store in a plastic bag in the refrigerator for up to 1 month.