And that is why most gardeners call Datura "devil's trumpet" and Brugmansia "angel's trumpet" - has to do with the orientation of the trumpet as to who appears to be tooting the horn. MoonFlower is an Ipomea, as is it's relative Morning Glory - different drug altogether.
Brugmansia will do ya, too.
Some of the South American varieties are known as "dream trees" because if you fall asleep under one, you will never wake up. The flowers have atropine and scopolamine in them, among other things. I'm told that the trees weep in hot weather, like crepe myrtles, and the mist they drop contains the intoxicating alkaloids.
The ground, dried flowers are alleged to be used to produce the notorious "burundanga," which has been the topic of several State Department travel advisories.