Everyone knows just what to do with onions and garlic, fellow members of the allium family. But for many eaters, leeks are a puzzler: Do you eat the bulb? Do you eat the leaves?

The answers are yes and yes, mostly (the dark green outer leaves won't hurt you, but there's little else to recommend the toughest and least flavorful part of the plant.) That's almost all you need to know about the nutritious, overlooked vegetable, but here are another seven facts to deepen your leek appreciation.

1. Leeks look like bulked-up scallions, and taste something like them, too. They're sweeter and milder than onions, although the wild variety, listed as "ramps" on restaurant menus and plentiful in southern Appalachia, are famously pungent.

2. Also like an onion, a leek isn't of much use whole. The most common preparation involves chopping the white base and light green leaves into quarter-inch slices, which can be sauteed, boiled, braised or served raw atop a salad.

3. Nero so loved leeks that his subjects called him Porophagus, or leek eater. And he wasn't the only leek devotee in the ancient world: The vegetable was popular in Egypt and Mesopotamia. Phoenicians traded it to the Welsh, who adopted it as a national symbol.

4. Leeks are packed with vitamin A, vitamin K and sulfur-containing nutrients. Eat up.

5. When shopping for leeks, look for firm, straight leaf sheath bundles that measure no more than 1-1/2 inches around. Avoid yellowing leaves and bruised bulbs.

6. Leeks should be stored, untrimmed, in the refrigerator. They'll last for about one or two weeks.

7. Despite the fame of vichyssoise, the French weren't traditionally fond of leeks, which they referred to as the "asparagus of the poor." The cold potato-leek soup is a relatively modern invention, developed in 1917 by the Ritz-Carlton's head chef as a tribute to his grandmother's soup, which he used to cool with milk.