I've had these for about 2 to 4 years now and nada. I water and keep them moist. Those that are mounted I water 2 to 3 times daily. I also use a 20-20-20 fertilizer for 2 weeks, off one. Any suggestions? They are sikkemenses (sp?), frostii, and the last one I forget. Please look at my list to find out. I think one is recognized as a Cirh.?