Discoloration of Onc. Pseudobulb...Is it Rot?
 

Please take a look at the discoloration of this pseudobuld. The tag reads Wils. Red stars ‘Rooster’ which I received as a gift, so I’ve had it now for about 3months. All my orchids are inside due to the unusually cold winter here in Florida. I keep the ceiling fan running on medium and try to keep the humidity around 53. I recently added a Wonderlight 160w for more light for the Onc. and Catts. to far from the window.

Here’s my question, is this some type of rot? It’s not soft to the touch and the rest of the plant is not showing signs it’s in trouble; however, this spot is growing. What should I do? All suggestions are welcomed.

That is rot.

I'd remove the pseudobulb with a pair of sterilized cutters immediately.

If the potting medium is old, I'd repot it too.

Check for root damage in the process.

If there's a root ball around some old potting medium in the center, I'd remove that too.

Should there be a lot of dead root, I wouldn't remove all of them. I recommend removing a few of them so the plant still has a way to anchor itself into the pot.

Ok, so I removed the pseudobulb and gave it a good soak in a physan 20 and tepid water bath. I packed the wound with cinnamon and re-potted (roots looked really good). I'm trying to learn from my mistakes, so what do you think caused it? No other orchid in the collection had this problem. Should I increase air circulation?

sounds like you did all you could...gl with it!

Sounds good.

1. How much are you watering?

2. A little more air circulation doesn't hurt.

I usually water when the first two inchs on potting material is dry, but this winter, I’ve been watering once every 7-10 days for larger pots and once a week for everything in 4in pot. This plant was grouped with the larger pots (really only in 5inch).

Try reducing the amount of water it receives just a bit more. Especially during the warmer months. See if this helps out in the future.

Thank you! :)

I'm sorry I meant to say cooler months not warmer months.

I apologize.

So it's supposed to be:

Wet spring/summers.

Slightly drier fall/winters.