I agree with Brooke. I got these on my C. walkeriana during some cooler, rainy weather and treating them a couple of times with the Isopropyl alcohol stopped the infection in its tracks. The spots won't disappear but they won't spread once treated.

Thank you guys, I'll try cleaning the leaves with alcohol and won't use peroxide on the roots. Quick newbie question: I usually spray the roots of my orchids during repotting with hydrogen peroxide for cleaning up any possible rots. Does anyone have a better solution which is not toxic to small animals (I have a cat).


Sent from my iPhone using Tapatalk

I never use anything on my roots when repotting. I rinse them off under the faucet. When roots are bad it is usually from over watering, not a contagious rot.

Brooke

With some of the orchids that are more prone to having roots rot if damaged, I soak them well before the potting and then carefully put them in dry medium and don't water for a couple of days to give the roots a chance to heal. This has worked very well for me.
Good luck!

I don't put anything on my roots either. I removed any dead, rotten ones and then rinse well. If the plant is really root challenged I will give It a soak in seaweed water for an hour before re-potting. I then don't water until dry or nearly dry.