Bacterial Brown rot

[Joaniep]

Hi,
My phal seems to have bacterial brown rot : It developed a soft brown area on a leaf, which I removed and applied cinnamon to along the cut edges. I now see another area on that remaining leaf. I cut that away with a razor which I discarded. What to do??
The bottle of physan 20 says for orchids to add 2 tsp. per gallon for a spray. The article here on pests and diseases says 12 tablespoons per gallon!!!!!!!!!!
Which is correct? What should I do to save my orchid?

Thanks. for any help you can provide

[Cynthia, Prescott, AZ]

Don't ever go over 1 Tablespoons (T) per gallon. I have done damage at a level only a little higher than this. Physan data sheet that they pass out says:
1 1/2 t/g for spraying seedlings once per month or a 2-5 minute soak out of flask
2 t for spraying adult orchid plants once per month or when desease other than rot is evident
1 T for soaking plant 2-5 min bareroot at repotting
1 t per 3g during cool weather, spray at first sign of spotting on flowers.
There a further suggestion about rot, but it is to remove the mix and soak the plant for 10 min in 1 T/g, but I don't think you should go to that extreme, and I don't think Physan is that good for rot. I think if this is continuing, you should look at your culture for the plant. Are you growing it too cold? You may want to cut off the bad spots with a larger margin of good leaf. Cynthia

[Joaniep]

Thanks for all the information Cynthia. You are always so very helpful