Question
Last summer we visited Europe.  In Austria - Graz, to be exact - I noticed many gardens had banana trees growing.  Having lived in Jamaica for the best part of a decade, I recognized them right away and was astounded that they grew the same height as in Jamaica.  

I asked how this could happen.  The answer was - in the fall, cut them to the ground and cover liberally with mulch or straw.  In the spring, they pop right up again.
I was astounded.

I have a large Bird of Paradise that I'm growing in a pot indoors.  I was thinking of doing that very same thing.  
We live in the Toronto, Ontario area - I'm not sure what zone that might be.  What do you think my plant's chances of survival?

Answer
Hi Erika,
Thanx for your question.  There are several varieties of banana that can be overwintered in some temperate climates.  Musa basjoo is one.  Check out this link from the University of Illinois.

http://web.extension.uiuc.edu/macon/palette/070610.html

I used to use tropical bananas out in the yard because their root system is shallow and they are easy to dig up.  Cut the tops off of them and wrap the root ball in a plastic sack.  Store in a cool but not frigid, dark, dry basement for the winter.  Midway through winter, throw a can of water on the root ball.  In the spring after the ground has warmed back up, plant it out and it will leaf out again.  We did this with bananas for many years here in Kansas.  As far as the bird-of-paradise goes, I had one of those and it definitely will not survive a Toronto winter (you are in USDA Zone 5).  Even with mulch, the long, carrot-like roots of the bird-of-paradise will not tolerate frost or frozen ground.  I hope this helps.
Tom