The missus bought herself one (on my suggestion). Seems a popular enough plant, for all that I've never heard of it before. Anyone else know anything about these things? Has she just bought a weed?
they're lovely though. My mom has a part of her garden set aside for such things. Weed grasses, thistles and whatnot. I don't know if your thistles will spread, but you may want to plant them somewhere confined, a garden lined with railway ties or rocks just in case?
I like to check this site now that I've found it...if it's on there I either don't get it or I make sure it's well confined. Canada invasive species list