Produce Guide: How to Pick and Prep Vegetables

When it comes to picking and prepping vegetables correctly, it’s important to know the growing method, signs of freshness and even proper color of your favorite veggies. Before mixing up that salad with greens, peppers, tomatoes and radishes, learn some harvesting clues—such as peak seasons of vegetables—to ensure your meal is fresh and clean.

It’s easy to admire the tall stalks of corn in an open field, but it’s a bit more challenging to understand the harvest growth of this vegetable. Corn crops have a time limit when in season because they usually ripen 20 days after the first sight of silk strands, says David Marguleas, executive vice president for Sun-World, a produce farming company based in Bakersfield, Calif. Before cooking up your corn on the cob, make sure that it was picked three or fewer days before to enjoy its peak freshness.

If you don’t have access to a fresh garden or farmer’s market, take special notice of vegetables purchased at a grocery store. When choosing peppers, Marguleas suggests looking for the firmest pepper on the shelves. “There shouldn’t be any give when pressing against the skin, and their color should be vibrant with a slightly glossy shine."

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Although watermelon is often thought of as a fruit because of its sweet taste, it is also a vegetable. When choosing a watermelon, it’s important to lift and assess its external texture to make sure it has a solid feel to it, says Marguleas. There should also be a bright yellowish portion on the skin that originates from where it sat on the garden floor, he adds. Luckily, there is no rush to cut into a fresh watermelon because it stops ripening after it is picked.

As one of the most popular additions to a sandwich, fresh tomatoes are in demand throughout the year. To pick a ripe tomato, look for a bright color with no signs of bruising or discoloration, says Marguleas. Since tomatoes can give when you slice them, use a thin, serrated knife and gradually saw through the skin instead of firmly pressing downward. Scoop out the seeds and dice into quarters for the freshest portion of this tasty vegetable.

If adding spice to your meals requires the freshest garlic, take a close look at the papery skin. Make sure that the cloves are tightly held together and the skin is dry. To lock in the vital nutrients of garlic that heat can destroy, chop and crush the garlic 10 minutes before adding to heat, recommends Mira Calton, nutritionist and co-author of “Rich Food Poor Food” based in Nokomis, Fla. Next, add garlic to a recipe 15 minutes before it is ready to be served to reduce long-term heat exposure.

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For the freshest fungus, mushrooms without bruising are the best choice. When inspecting this tasty vegetable, make sure the gills on the underside are tight since gills spread as mushrooms age. Since mushrooms age quickly, refrigerate these healthy veggies and store in a paper bag to keep fresh. Although you can eat them raw, cooking mushrooms packs a healthy punch, says Calton. “Agaritine, a potential carcinogen most concentrated in mushroom caps, decompresses readily upon cooking,” she says.

Before tossing a delectable salad, know how to pick and prep the best leafy greens. First, inspect broccoli, lettuce, spinach and collard greens, which should radiate green, not yellow. Make sure, too, that the stems are not dry, split or tough. Bok choy and other leafy greens should be refrigerated in an open bag, says Amy Klein, executive director of the Capital District Community Gardens in Troy, N.Y. Avoid using biodegradable bags because they suck the moisture out of leafy greens, she says.

It’s common knowledge that a soft avocado is a ripe avocado, says Klein, but how do you know if it is too ripe? Klein suggests tearing off the stem to inspect this vegetable. “If it’s light brown underneath, the avocado is perfectly ripe,” she says. “If it’s black, then the avocado is over-ripe.” To prepare, slice it in half, grasp the skin and pull it away. Store ripe, peeled avocados in the refrigerator but not for long, since their shelf life is two or three days.

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During July and August, potatoes are in their prime. When shopping around for these fresh veggies, Klein recommends rubbing the skin with your finger. “If it comes off easily, it means you have a fresh potato,” she says. Potatoes can be stored for many months if they have not been exposed to moisture. Resist the urge to wash them before you store them. Once you’re ready to dig in, simply peel with a potato peeler or slice and dice with the skin on before cooking.