South would probably be the best bet but honestly the ones that overwinter here are in a spot which should kill them each winter. They're out in the open, heavy soil, poorly drained and only about six inches before you hit shale. We were well below zero in the winter with little to no snow cover and the one clump easily had 9 bloom stalks.

Try tucking in a plant or two in a couple different spots, that way you increase your chances!

About 10 years ago, I forgot to bring them in. They came back the next year and every year since. Last fall, I planted another batch with the intention of leaving them out. They are blooming. Some are near the warming foundation of the house, many are not.

Warmer zone, but I have them in two different places - they have come back and seem to be rather aggressive on the bulblet front. There have been a few threads about this where people have said the only ones that don't come back are the "hardy" ones. :)

I'm in southwest Michigan and plan to leave mine out this year, I wish I had time to do all that it involves bringing them in but I don't! I'll be hoping and praying for the both of us :)

Maybe take in many just once more and see how the ones left survive.