Picking at the Peak
You spend all season tending to the needs of your vegetable crops—feeding, weeding, watering, and handpicking pests—and then comes the moment of truth: Has the fruit of your labor reached its peak of ripeness? We asked vegetable experts and market growers to share their secrets for selecting perfectly ripe produce and keeping it fresh. Take this guide with you to the garden (or the farmers' market), and you will fill your basket with the most flavorful food possible.
The Science of Freshness
A fruit or vegetable's existence depends on respiration—a physiological process in which starches and sugars are converted into carbon dioxide, water, and other by-products. Respiration continues after harvest, diminishing the starches and sugars that add flavor. Moreover, at harvest, vegetables are removed from their main oxygen source: their roots. This means postharvest respiration may be anaerobic (occur without oxygen). In anaerobic respiration, starches and sugars are more likely to be converted into ketones, aldehydes, and alcohols than in aerobic respiration. These compounds hasten the death of plant tissue and decrease the quality and flavor of fruits and vegetables. Gardeners can manage respiration—and the freshness of their produce—by using proper harvesting, handling, and storage techniques.
Beans Pay attention to your pods. Fresh, juicy, bright green pods indicate tasty broad, lima, and green shell beans. Snap beans should snap easily and have crisp pods with pliable tips.
Broccoli and Cauliflower
Crucifers need to chill out for the best flavor. Pick them in the morning, cool them down immediately with ice or ice water, and then refrigerate, says Helen Harrison, Ph.D., professor of horticulture at the University of Wisconsin.
Cut cabbage heads off the stalk when they feel solid and hard to the touch.
Here's a crop that can get better with age. Sugars increase in growing carrot roots for up to four months. This means tasty carrots can be harvested well into autumn in most areas. "You do have to watch out for splitting when it's real hot and dry or when it's too wet," says Pete Cashel of Terrapin Hill Farm Organics, in Harrodsburg, Kentucky.
Sweet corn—one of summer's most perishable crops—tastes best fresh from the garden (we're talking minutes here) and dripping with butter. If you can't prepare it directly after harvest, cool the ears on ice and then refrigerate them.
Harvest sweet corn about three weeks after the first silks appear. You'll know the corn is ready when the ears fill to the end with kernels and the silks and green husks become dry. An opaque, milky juice will seep out of punctured kernels.
Frequent harvesting of cucumbers helps the vines produce new fruit. Why? Because one actively growing cucumber needs 40 percent of the plants photosynthetic output, says research from North Carolina State University.
Ripe eggplants drain the plant's resources. So know what you grow and harvest eggplants when they reach the proper size for their variety.
Leo Keene, who with his wife, Jean, grows about 45,000 bulbs of garlic at Blue Moon Farm in Richmond, Kentucky, suggests using a square-tipped spade to dig garlic. "Your goal is to sever the roots," he says.
Dig about 4 inches away and parallel to the plant. Sink the spade 6 to 8 inches into the ground; then push to a near 90-degree angle, cutting the roots and lifting the garlic. Knock the dirt from the bulb and shade it immediately. "Garlic is easily sunburned," Leo Keene says.
Hot weather is a lettuce crop's worst enemy, because it causes bolting (the formation of seed heads) and bitter- tasting leaves. Luckily, you can often harvest tasty leaves from both head and leaf lettuce plants right up to bolting, Cashel says.
When buying lettuce at farmers' markets, look for vendors who display their lettuce on ice or in coolers, Cashel advises. And don't be afraid to ask if the vendors grew their own crops.
Pure melon flavor is short-lived and best enjoyed fresh. The more mature the melon, the less time it will keep in the refrigerator, though you can try freezing melons to preserve their summery sweetness.
Do you crave homegrown produce in the winter? Then grow onions—they store for months when properly handled. Dr. Harrison says you should wait until the tops fall over to harvest, then gently dig up the whole plant and dry in a protected place.
The word pea should be synonymous with picking. Regular harvesting is vital because peas left too long on the vine arent as sweet and can impair the growth of immature pods. Sugar snap peas and traditional shelling peas should be fully formed but not overly large.
Personal preference dictates when you pick peppers. Most peppers start out green and turn different colors as they mature. Harvest sweet peppers, such as bell peppers, and hot peppers at the degree of color you desire. And take care when picking—pepper plants damage easily.
If you want to store potatoes, they need to be cured, says Jo Ann Robbins, Ph.D., University of Idaho extension educator. In this instance, curing doesn't refer to fixing a malady; rather, curing is the process that toughens potato skins for prolonged storage. Dr. Robbins recommends waiting one to two weeks after the plant tops have died back before digging the potatoes for storage. This cures the potatoes in the ground. Just be sure to dig them up before frost.
Baby spinach is all the rage for a reason—the smaller leaves maximize flavor. "Most spinach tastes really good when it's 3 inches long," says Sondra Feldstein, who grows spinach and other vegetables on her farm in Bondurant, Iowa.
Summer squash are notoriously prolific producers. "In some small towns, people lock their doors during the summer to keep out the zucchini" deposited by gardeners with a surplus, Feldstein says. Unless you want squash as big (and tasty) as baseball bats, you should pick them frequently.
Harvest tomatoes when the fruits are fully colored. At the end of the season, pick remaining mature green or pink tomatoes, put them on a plate or in a paper bag outside the fridge, and let them ripen.