collar rot

[wintergirl]

Here is a site with treatment for the collar rot or Southern Blight from The St Augustine Orchid Society:

Treatment: Systemic fungicide like thiophanate methyl (like Cleary's 3336 or Banrot). Sterilize benches and surrounding area with bleach or pool algaecide.

Prevention: Normal sanitation, good air movement and lower temperatures (if possible) may help reduce the spread of this disease. The pathogen is most active in warm weather when humidity is high.


Orchid Diseases