Vanilla planifolia showing signs of root rot - what can I do?

[Laura75]

Hi, I'm Laura and I'm new to this forum. I hope you guys can help me out. I have a vanilla planifolia that I ordered on Amazon - a beautiful specimen, with three stems. The problem is that two of them have suddenly started showing signs of root rot: they are thinning and drying out at the base, the leaves at the bottom are turning yellow then black and the aerial roots further up the stems are withering. The third stem still seems to be in good health. I have been watering once a week as per instructions. Any ideas on what do do? The disease seems to be progressing quickly, so I think I need to act fast. Is it possible to save the diseased stems by cutting them off and re-planting in a new potting medium? And what about the (for now) health stem? Should I leave it where it is? Last question: how do you make an ideal potting medium for this kind of orchid? Many thanks in advance.

[estación seca]

Welcome to the Orchid Board!

What are your temperatures day/night? Humidity? What kind of light?

Vanilla prefers warm to hot temperatures, high humidity and bright light. The medium should not dry out. Once a week watering is probably not enough. Without enough water the leaves turn yellow, then black, then fall off. Without high humidity the aerial roots quickly die. It is not always a good house plant because most homes are not warm enough and the humidity is not high enough.

[Laura75]

Thank you for your reply. I live in Rome, Italy, where in summer indoor temperatures range from 24-34. Right now (21:30) it is 28.5 degrees and 34% humidity. I have never misted. The vanilla is in the warmest and lightest room in the house, but not in direct sunlight. I'll try to attach a couple of photos for additional info.

[estación seca]

It looks better than I expected. The temperature is fine. The humidity is lower than it would prefer but not too low for it to grow. I believe the leaf drop was caused by changing to a different environment.

What is your potting medium?

[Laura75]

I didn't repot it when it arrived, so I am not really sure. But there is sphagnum moss on top and then I think (fear) it is just ordinary potting soil. What do you suggest I do?

[estación seca]

I would move some of the moss and find out what is beneath. How often to water will depend on what it is potted in.