Exotic flowering mystery seeks ID

I confess, it was me but there were a few and this one had dropped off the plant onto the dirt. I didn't think anyone would mind that one? 

Anyway I planted it, this was about 2+ years ago and now it has produced some lovely flowers. It likes being south facing and grows in garden, ashey soil, so a bit of a lucky minimal maintenance plant! Yipee! It does look fab though, so I need a name, a proper latin one, Herbet won't do! Anyone out there know? Thanks x