This was growing in Cornwall on cliff faces in long strips. I took a little snippet, potted it at home and its now tripled in size.
Problem is, it has tiny, sticky specks of a clear liquid on it. Also, occasionally I notice small (2mm) semi-circular, green, half shells attached to the stalks, and 4mm, white cocoons which look like a tiny bird poo! I remove these added things as soon as I see them, but I'm tempted to bin the whole plant if I have a colony of something growing on it!?!