Picking at the Peak

Expert tips on how to pick your fruits and vegetables at the height of freshness.

By Matt Ernst

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. 
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. 
  • Harvest full-size snap bean pods before the beans begin to bulge. 
  • Pick daily for a continuous supply. 
  • Fresh tastes best—harvest beans right before you use them. 
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. 
  • Harvest compact, white, smooth cauliflower heads. 
  • Select blue-green broccoli heads and harvest them before the small, yellow flower buds open. 
  • Leave the small leaves on broccoli stems intact—they're very nutritious. 
Cut cabbage heads off the stalk when they feel solid and hard to the touch. 
  • Want to keep mature cabbage in the ground a bit longer? Pull or twist the heads to break off some of the feeder roots and limit water uptake, and they will be less likely to split. 
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. 
  • Dig full-size varieties when roots are ½ to 1 inch in diameter. 
  • Harvest storage carrots just before heavy frosts. 
  • Avoid selecting cracked or split carrots when buying at farmers' markets, says Cashel. They often have a bitter rather than sweet flavor.