I grew some of the hottest habaneras I've ever had myself. Here's the secret - get a bag of Miracle grow potting soil, and place it flat inside of a black plastic garbage bag. Lay this where you there will be lots of sun. Poke holes all the way through the bags so the water can get out. Cut 2 or 3 holes into the potting soil about the size of your fist to plant the seeds or plants.
Give them a little water twice a day, and stand back and wait. The sun heats the garbage bag, which heats the roots, which keeps them producing the capsaicin that make the heat.
None of my freinds could believe I grew peppers that hot here in Ohio.