As for the bulbs, I've planted them in nearly frozen ground and they've been just fine come spring. I feel they'll fare better out there than inside.

As for plants in containers, if too late to plant, you can safely overwinter in their containers if protected from repeated freezing and thawing. I usually sink the pots into the soft earth of my winter-vacant vegetable garden, or bunch them together and cover with a generous layer of leaves - shredded or not. That being said, last winter we had so much to do after Sandy ripped through, that we didn't get a variety of small trees, shrubs and herbaceous perennials into the ground or mulched and, to my surprise and delight, not a single plant perished. However, I don't recommend that practice.