My friend has sent me a photo of one of her orchids, she has had it quite a while. It is not in flower and the top big leaf is half blackened from the tip inwards. I asked if she had been watering a lot and she said more the opposite. Anyone got any ideas. Annlouise
I'm no orchid expert, but I lost several Cattleya orchids to Black Rot fungus (Pythium ultimum and/or Phytophthora cactorum). Look at Google Images for examples. It can affect other types of orchids, but Cattleyas are particularly susceptible. If this is what you have, it will probably spread to other leaves and stem sheaths, unless you take preventive action. I'm not sure what's best, but I've been keeping the fungus under control in my last Cattleya by removing the blackened parts of the plant as soon as I see them.
Ok thanks vitog, will pass this info onto my friend and make a note of it myself for future reference, I have 7 orchids.
