Here in zone 5 (5B or even 6A) this ornamental kale returned for a second year, becoming quite monstrous. We had heavy snow cover here in Michigan most of the winter, but I have never seen this kind of regrowth before. I am always pleased to see these kinds of anomalies in the garden. It keeps things interesting!
A second kale also returned (bottom right), out of the three that had been planted the previous fall here in client P's front yard, but remained more modest in size.