Posted: 20/10/2013 at 14:49
I have had one of these for about a year now and the whole thing is looking decidedly green. Mine is probably in the worst possible position, in mainly shade quite close to a massive pine tree, so no doubt too dry. We do have acid soil though. I was going to give it a good pruning back and keep it well watered. Does anyone know which factor causes it to turn black?