I've grown those in the garden from seeds shared by other DGers. And there is a double purple in the seed trade.
Area behind us was bulldozed for construction. One year there was a good acre or two of absolutely covered with white Datura plants, where had been pasture with the occasional one. It is a genus that can take advantage of certain situations, with "wild abandon.".
Datura seeds can live for years. Oh, wow, so can threads. Never mind. I got rid of my datura and after about 5 years quit seeing seedlings pop up. I cannot imagine having an acre, and it is poisonous to cattle I believe too.