Worldwide, there are more than 7,500 known varieties, 100 of which are grown commercially in the US. They all differ in shape, size, color, texture, aroma and flavor.

Also known as Swiss chard or rainbow chard, you can eat both the leaves and stems. You want crisp, perky and glossy leaves, with firm and healthy stems.

Fennel bulbs should be whitish-green, firm and heavy for their size, with no brown or mushy spots. If the feathery green fronds are still attached, they should have no signs of wilting or dryness.

Mature garlic heads should have a paper-like skin that covers all the cloves, which ideally are firm and free of mold or bruises. Green garlic has a light green stalk and white bulb at the base with darker green tops.

When shopping for kale, stay clear of wilted or browning leaves. Leaves and stalks should be firm and dry instead of wilted and mushy.

Common leeks look like giant scallions and have a mild onion-y, sweet flavor. Look for leeks on the smaller side, 1-2" in stem diameter with very dark greens that have no yellowing or wilted spots.

There are several varieties of mushrooms and they can be purchased fresh or dried. Look for fresh mushrooms without slimy, moldy or black spots.

When purchasing dried onions, avoid brown or mushy spots and choose onions that feel heavy for their size without any signs of sprouting.

No matter the variety of potato, be sure to store them in a cool, dark place with low humidity where they can be stored at least one month and up to three months.

Rapini, or broccoli rabe, looks like a leafier version of broccoli. Both the leaves and florets should be deep green without yellow spots.

The rutabaga is a sweet root vegetable that looks a lot like a large turnip with pale yellow flesh. Rutabagas are often sold with a protective layer of wax that improves shelf life, so peel them before cooking.

Although you can sprout many seeds, the two most common sprouted types are bean and alfalfa. Look for sprouts that are perky and smell fresh. Avoid any that smell off or that appear slimy or wilted.

Winter squash is actually harvested in autumn before a hard frost and stored for later. Squash comes in many sizes and colors and may even have decorative warts. Avoid squash with visibly broken skin.