Hello, I just found this forum via google. It seems to hold a lot of information. My favorite plant is the banana plants.
I live in Zone 5b, and I have overwintered Musa basjoo since 2003 outside. The plant dies back, but the roots remain alive. Each year the plant reaches the height of the roof eaves which is about ten feet approx. And every year, it is a thrill for me to see it grow.
Now there is a secret that I have which may contribute to my success. My house is heated by water pipes in the slab. This means that despite my best effort, the ground is warmed up throughout the winter. I first discovered my treasure back in 1997 after some calla lilies came back after the winter of 1996. Being a new gardener, I thought nothing of it for a couple of years until I read how they should NOT be coming back in Michigan. THEN I decided to exploit the house. The musa basjoo was one of the first plants. I tried musella lasiocara (sp?) which survived two years, and some other plants. Some survived a couple of years, and some did not meet what I desired. Now after these years, I do have some elephant ears that come back, numerous types of callas, musa basjoo, reed grass, bamboo, and some cannas. I did have sugar cane survive for about three years, but it has died. Since it reached ten feet, I did not replace it.
One of my other favorite plants which has turned into a weed...although a pleasant one...is tetrapanax papyrifera 'Steroidal Giant. I got it here back in 2004.
PDN -- Tetrapanax papyrifera 'Steroidal Giant'
It started as this small little plant which has reached gigantic proportions of eight to ten feet every year depending on the amount of rain. It has spread by root up to ten feet away from the plant. Every year it dies back and returns with vigor the following spring.
Last year in the front of the house, I planted a mysterious banana plant that was mistakenly sent to me instead of Musa itinerans. It is either Musa zebra or Musa sikkimensis. I covered it and am hoping for the best.
So, this is me and bananas (and other tropical plants).