I received this plant as a "rescue" about 6 years ago with no information other than "it had pretty purple flowers". It finally started flowering a couple of years ago but the flowers are very short lived so I've never managed to get any good photos until today. I'm pretty sure it's some type of ground orchid and it was suggested it might be bletilla striata but the form is totally different. The plant is now thriving outside in zone 8ish, and even starting to spread. First 3 images are of my plant, the last 2 images are bletilla striata from Wikipedia.
Thanks for posting that. I saw one at UBCBG four years ago, but remembered nothing about it. Nadia posted it four years before that at Rare flowers at UBCBG. I have managed to forget it twice. the colour was more blue than yours. Zingiberaceae, ginger family, really surprising to me - the flower looks so much like Impatiens.
