You can eat a chili pepper at any point, whether it’s red, yellow or green. Chilies that have been on the vine for a short period of time tend towards spicy and tart while mature chilies have a milder and sweeter taste. Red chili peppers start out small and green, and grow into bright red peppers within three months, though the exact colors and time to maturity depend on which one of the dozens of breeds of chili pepper you are growing.
Ripening Chilies on the Vine
Leave in a sunny place and water frequently – bring the plant indoors or pick the chilies whenever there is a chance of frost. Chilies grow much slower when night temperatures are below 55 degrees Fahrenheit.
Check peppers for a bright to dark red color, which indicates that the pepper is ripe. Depending on the type of red chili pepper that you are growing, this stage can be anywhere from 70 to 85 days.
Harvest when the peppers reach the desired color.
Ripening Chilies in Your House
Place the chilies that you wish to ripen further in a bag or container with a ripe tomato, either on your counter (faster ripening) or in the refrigerator (low temperatures slow ripening). If you use a plastic bag or container, punch holes in the bag or use a breathable container so as to facilitate air circulation.
Wait a couple days, but no more than two weeks (tomatoes last for about a week after harvesting while peppers last for two; you should remove the tomato after a week). Ripening tomatoes release ethylene gas, which stimulates ripening in other vegetables.
Remove the chili when it is a bright or dark red, though keep in mind that you can consume the chili at any stage.