Good info from imafan26. I grew ghost peppers a couple years ago and they were ungodly hot from the get-go whether green or ripened longer. Same with all the Habanero, Trinidad Scorpion Butch T's and other hot peppers I've grown. I've got some Carolina Reapers in the ground right now and for some reason they are not growing all that well, especially for being in the ground for a couple months now. This was my first attempt at them and if they fail, which seems likely, I'll try again next spring with new seeds.
One thing I did discover about the hot peppers. It seems the hotter the variety, the longer they take to produce, but when they start, they come on like gangbusters. Last summer I had 3 habanero plants and I was picking upwards of 50+ peppers a week off them. The Butch T was producing, but at a much slower rate.