Hardy Tropicals UK

I'm interested in getting cannas but I want something to last but as my title suggests which is the hardiest canna?

Depends how you winter them, but all the ones I've ever had seem very hardy. They come back if left in the ground, or are quite happy neglected in a dry pot over the winter in a frost free place. Just go for the leaves/flowers that you like the look of.

As always it depends on your location and garden. I personally don't leave any canna our over winter but I'm in Yorkshire. As to the hardiest I'm really not sure. They're easy to over winter. Just place let the leaves die back and don't let them dry out and then give lots of sun and warmth in spring.