Question
I am new to raising orchids and recently purchased a Cattleya from Home Depot. I currently have the orchids in the house due to the cold weather we have been having. The orchid looks healthy and has a spike with 3 blooms waiting to open. The problem is the potting material is covered with what appear to be green moss and is keeping the material extremely wet. Should I wait till it is done blooming before replanting and take a chance on rotting roots or repot now?
Thank you for your help.  

Answer
Hello Pat,

From your description of the potting material, it sounds like it might be sphagnum moss.  There are some orchid growers who use sphagnum moss to pot their orchids because it stays wet longer than most other potting materials and thus they do not need to water as often.  

The major problem with the moss is that it does stay wet for a very long time and that can cause the roots to rot.  This is especially true for persons who like to water on a regular schedule.  

The trick with moss is to allow it to dry out somewhat between waterings.  The problem is that although the top might look dry, within the pot it may still be somewhat damp.  Also, moss tends to rot or go bad fairly quickly and should be replaced annually.  

Since your cattleya is about to bloom, I would suggest waiting to repot.  In the meantime, try to allow the moss to become almost dry between waterings.  Try lifting it to see how light or heavy it feels, if it still feels somewhat heavy, wait.  

As for repotting, it is best to wait until you see new root growth activity before doing so.  Cattleyas can be finicky about this part, some will even show their displeasure by going into a funk for some time.  But, if it makes you feel better, after it finishes blooming try removing it from the pot and remove just a little of the moss to loosen it and  then putting it back in.  

One neat trick would be to take the cattleya out of the pot and putting it into the same size ordinary clay pot.  Clay pots will draw out excess water from the moss.  Just be sure it is one that has a natural finish, not one of those decorative kinds with a shiny glazed finish on the inside or outside.  

Hope this helps.  Good luck.

Jim Kawasaki
San Jose, Ca.