All baby peppers start out some shade of green and change color as they mature. Some peppers stay green until they mature to yellow or red; others may turn white, lilac or purple before maturing to red or yellow. You can eat peppers at whatever stage you prefer, but the color change in ripening peppers is caused by the breakdown of chlorophyll, which coincides with the maturation of the seeds. Sugars and other flavor compounds also accumulate during the final stages of ripening, and vitamin C content often doubles. So, fully ripe peppers taste better and are more nutritious.

Consider a couple of examples: ‘Sweet Banana’ is pale yellowish-green when the fruits are immature; they slowly change to yellow, then orange and finally red. ‘Purple Beauty’ turns bright purple, but when fully ripe, the fruits darken to deep purplish red.

If you want maximum flavor and nutrition in sweet peppers, it’s best to grow varieties that waste no time changing to their fully ripe color and flavor. Varieties that mature to red far outnumber those that mature to orange or yellow — a few fast-ripening red peppers to try are ‘Gypsy,’ ‘Lipstick’ and ‘Ace.’ Peppers picked when they have just begun to change colors will continue to ripen indoors when kept in a warm place.