Hate to see unanswered questions, so I tried to find out something. I learned a bit--google B. hiemalis 'Elatior' for a little--but didn't learn anything I think would help you. One entry referred to them as 'annual', which means they're a little tricky and not very expensive (at least in the opinion of growers) so they think you should grow them until they start wanting to go dormant and then pitch them. Some years ago I tried some and I know it's not that hard to keep them, but they'd prefer a cooler climate than I have. They go dormant. If you're lucky they'll come back from dormancy. They're winter bloomers and summer dormant I think, which is why they didn't like it here much--too hot in the summer. That's what I remember anyway--it's been years.