I've had pretty good luck winter sowing liatris seeds. They bloom two to three years from seed, if you can be patient. Liatris ligulistylis is a tall one, I have a few that look like they'll bloom this year. I had to stake the tallest ones because they looked like they could topple over. Also this one is said to be a monarch butterfly magnet. I winter sowed mine in 2013 and three of about a dozen of them look like they'll bloom (a fourth one broke, otherwise I would have four wanting to bloom). I suspect next year they'll all bloom. Now all I need are monarchs.
