Cattleya Claesiana hybrid with black patch on pseudobulb
 

Hello All,

I had a question about a cattleya orchid I have.
The orchid is growing well with many sheaths and a completely healthy root system. I have a concern however that there is something wrong with one of the pseudobulbs.

One of the pseudobulbs has a black region on the top of the pseudobulb near the leaf axil/junction. The spot is very dark, but also firm. There are no spots on the leaves.

The orchid is being kept outside in intermediate conditions with good air movement. One night this week the temperatures dipped to 56f.

I was concerned this could be a fungal rot like Pythium and travel down and kill the plant yet, the patch seems to be the same firmness as the bulb and the rest of the plant is healthy.

I would not want to cut off a perfectly good bulb and introduce a new point of infection so I would prefer not to have to remove this growth if possible.

I've seen very black coloured patches on a couple of bulbs of one of my catts, which had come in the mail - many months ago. Unlike yours, these black bands are something like 1 cm wide ----- going fully around the bulb. However, like yours ----- truly hard region ----- does not spread, and nothing is wrong with the leaves. The plant keeps growing well, new leads etc.

But ----- like all of my plants that get sent in through the mail, I spray with systematic fungicide - regardless of their condition.

Your plant could be just fine. Maybe that noticed cold dip was the cause. If there's no spread, and bulb remains indefinitely hard - no softness in that region ----- then most likely no problem.