Serious gardeners/ingredient gurus: I'm perplexed. I've been growing poblano peppers and thai bird chiles this summer. Both are doing great. I've had a few mature peppers on the plant that I didn't want to pick because I was not yet ready to eat them. In my experience, poblano peppers are always green. But my ripe poblanos, left unpicked, turned red. The same happened to my bird peppers (although this is less strange to me since I've seen these peppers in red, yellow and green).
Anyway, my question: is this normal? Do poblanos (and other green peppers) generally turn red? And what does this mean for the flavor of the pepper?