The cayenne pepper is one of the most versatile members of the chili pepper family. On the plant, the peppers start off as green, gradually start to turn orange-red, and finally ripen to maturity as a vibrant red color. Cayenne peppers can be harvested at any time during this process, although the color of the pepper will affect its flavor and heat level.
Cayenne peppers are easy to grow; depending on your climate, they can be grown as annuals or perennials. If you have cold winters, you are better off buying them each year as annuals because they will not survive frost (southern California is the only place I’ve ever lived where I was able to keep them as perennials, but the Gulf Coast also has mild enough winters for them to survive). Cayenne peppers mature during the middle of summer. The plant will start to fruit (produce peppers) a few weeks after the plant puts out blossoms. As with any fruit, harvesters should look for peppers that are smooth, glossy, and free from blemishes, mold, blight, or any signs of pests.
Green cayenne peppers are ready to pick once they reach full size, which is about 4 or 5 inches long. They should be firm, medium- to dark-green, and have a slightly waxy texture. Green cayenne peppers are very mild in flavor and heat, and will be slightly bitter. The seeds are also lacking in heat, so they have little culinary value.
After a few weeks, the green peppers will begin to turn orange-red at the tips. This color will gradually spread up the peppers. At this time, the peppers will have a sweeter, fruitier flavor and be noticeably spicier than the green peppers, but still milder than the fully mature red peppers. The seeds and membrane will be quite hot, almost as hot as the seeds of the mature red pepper. Cayenne peppers at this stage are also popular with chefs as a garnish because of their interesting color contrast. This stage doesn’t last long, typically only a few days to a week, so orange-red peppers have to be harvested quickly.
When the peppers reach full maturity, they will be bright red and will often have a slightly curled shape. The peppers should still be firm and mostly smooth. Fully mature cayenne peppers have sweet and spicy flesh and are very hot, much hotter than jalapenos. The seeds and membrane are particularly hot, and care should be taken when handling them. The flavor of cayenne peppers will increase in complexity and heat the longer they are left on the plant. They can be left on the plant until the skin starts to wrinkle; after this point, the peppers will start to go to seed so they should be picked and properly preserved.
Cayenne peppers will continue to mature slightly for a few days after being picked; the process can be accelerated by placing the picked peppers in a paper bag. However, cayenne peppers are notoriously temperamental in this regard, and have a greater tendency to go bad if kept at room temperature. Ideally, peppers should be eaten the same day they are picked, but they can also be preserved in a variety of manners. They can be refrigerated for a few days, or even a few weeks if stored properly. Cayenne peppers also freeze well. Pickling is another option, and they can be pickled fresh or roasted and then pickled. Red cayenne peppers are often strung up and dried to make red pepper flakes or the ground red pepper commonly known as “Cayenne pepper,” a popular seasoning in Cajun cuisine.