I winter over Black and Blue salvia by cutting back and potting it up then putting in a cool dark basement room. Once a month I give it a small amount of water to keep tubers from shrinking. In the early spring I put it under lights for new growth and plant in the garden after the last frost date. Some of my plants have been wintered over three or four years. Editted to add: when I cut it back I cut it way back to just a short stem. That should make even a large one easy to pot up. This post was edited by mnwsgal on Mon, Nov 10, 14 at 12:10

Thanks fglavin, This year was a very bad year indeed for bananas. My tallest this year was only 12ft. tall,a basjoo. Most of mine only got around 6 or 7ft. tall. That late cold spell also claimed many of my bananas. I lost my largest a large red iholene that got nearly 20ft.the year before. It also got all of my velentinas. I had all of them mulched but they were already growing and the cold got them. I also lost my Yunnan bananas.I didn't loose any of my palms though.I have over 30 in my yard right now. I am trying many differant ones to test my luck. I have 29 cheesmani that I grew from seed last year to plant in the yard. I will be busy for a while when spring comes around. My house looks like a jungle right now.

I have not bought a Mandevillea in a long time, so have no experience in over wintering it. I did want to mention though that the plant that I have the most success with overwintering, is my tropical Hibiscus. They sit in a sunny West window all winter and don't seem to be bothered by the reduced sun, or the dry air. I pay very little attention to them and just let them get a bit of rest over the winter and when they go outside in spring, they perk right up and get back to performing. And if I've been good to them over the summer, when I bring them in the house, they usually will keep pushing out flower buds and bloom in the house for a month or more. I have an open flower on it right now and another bud still to open.

Thank you for the suggestion. I was starting to think of digging it again since that worked last year and I don't want to lose the plant. I'll be taking your suggestion. I think I'll pot it in really good potting soil and see if I can make it strong, and maybe see if I can propagate it from cuttings next year, then, indeed, I could try it in both places,out and in. That would be the best scenario. I am in a similar situation with a Dutchman's Pipe I brought from Houston area - no clue whether it is the hardy one or not as its been in a pot the whole time. I'd love to propagate that too. I have a really strong hunch it is tropical, though, and I'd love to have seeds or cuttings of the hardy kind, esp for the pipevine swallowtail. Going to keep that on my wishlist.