THUG ALERT! Even cutting it completely to the ground in early spring didn't stop it from taking over a trellis to either side in addition to its own space. When I put it in, I also didn't realize it was invasive -- and there's just no way to deadhead every bloom. I dug mine up, threw it out, and I'm still pulling seedlings out here and there 3 years later.
2021 update. still pulling out one or two seedlings each year!
Here in NJ it seems to grow wild. I am constantly pulling it out of everywhere.
It even has taken up home within my good Clematis. If you cant control it , it will over take your whole property just like wisteria.