Peas
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.
Peppers
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.
Potatoes
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.
Spinach
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
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.
Tomatoes
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.