Gee, I was about to post a similar question to yours. I'm new to growing Cattleyas too and recently got a bunch of small seedlings. 3 out of around 15 have died (leaves fell off and had back spot right above the roots) and several blooming size ones are having the same problem. The stalks are shriveling and getting soft. Think it is root rot? Some of my Cyms. do that too. I will be awaiting help from the other members on this too. Sorry couldn't help. Would be like the blind leading the blind.
