Deb, the one that is in the picture was at least 5 years old when I took that picture, so I've had very good luck with it. This was in my Utah garden though, which is zone 5a, so maybe that makes a difference? It did almost too well there, but boy, what a show every Spring!
Tara, you should give it a try! The nice thing is that it can be cut way back after blooming. This one covered many plants around it that would start growing about the same time that this one was done blooming. So, I'd cut it way back. It would often get a few more blooms on it, but didn't spread like it did when it first started growing. I miss that plant and need to get some for here!