I've had a small rosemary plant for a little more than a year. It lived outside all summer and has been happily residing indoors all winter. I moved it last week and noticed this strange pile of what maybe looks like worm castings in the dish underneath the pot. It seems to be coming out of the drainage hole in the pot itself. Anyone know what this is? If it's good or bad or what? I haven't seen any other signs of insects aside from this.