They need protecting from frost. I've had one for 3 yrs. The first winter I kept it in a cold greenhouse and nearly lost it, had to bring it indoors where luckily it recovered. Last winter I brought it inside before the first frosts and kept it in the porch which is unheated but frost free. I cut it down in spring and put it out again after the frosts. It's put on a beautiful show this year and is now in the greenhouse ready to go back in the porch in a few weeks time.
Good luck with yours, they are so pretty.

Thank you Seabird.
I love them. When we go to Italy they have them all over and they stay out all year round. The first time I saw them was over there and got one when I came home but they are always difficult to find around me so hope I can keep it this year. Thanks again Cranberry