Ive, think of yourself standing out in the desert sun at mid day in central Africa, someplace inbetween the Congo jungle to your south and the Sahara desert to your north. That is where these plants are native. They LOVE heat.
A couple of years ago, I had two kitty litter pans with about fifty baby Adeniums in each pan. They were covered with plastic. I forgot and left them covered, on my hot deck in full sun, when I went grocery shopping one day. The heat built up like in a car with closed windows. I think 'they' say 140 degrees. The (African) obseums cooked, boohoo, they all died, but the arabicums, those from Arabia, did fine! Most of our Desert Roses are obseums.
Heat is different for us than it is for Adeniums. But the same as us, they will sunburn if you take them outside for a whole day. Needs to be one hour the first day, two hours the next day, and add one hour each day.
