Hello members, this is the only Catt in my collection. I bought it with a sheith several months ago. The sheath has now turned completely yellow. It looks to have had a "spike" developing on the inside. Can someone tell me what I may have done wrong? It is grown outside and I live in Houston, Texas. It gets bright mottled sunlight all day and I water them weekly and it is now under a misting system that goes off 5 mintues a day four times a day.

Thanks!