Poinsettia

I got this poinsettia at Christmas 2014. Most of the leaves died off around the end of May. At which time, I decided to take it outside, and dispose of it in the garden waste. I put it aside, and forgot about it. A couple of weeks ago, I noticed that it had sprouted some new leaves. So, I watered it, and left it outside. It's doing better and better each time I look at it...