Ionocidium popcorn highland
 

My leaves are getting very yellow. Do you think it’s not the right amount of light?

The mix looks damp but boy by the looks of those shriveled leaves I'd have to say it needs a lot more water.....BUT.......be careful and watch it closely because overwatering can end in that exact same symptom so if you have been watering a lot then you need to back off and do just the opposite making sure the media is totally dry between waterings because you have been literally drowning it.

I don't grow too many of the Oncidium types (and most of the ones I have are mounted) so there is probably better advice coming.

I water once a week with a good 15-20 minute soak. It’s dry when I water it so maybe a short water 2 times a week would be better? I thought it was improper lighting that was making the leaves yellow. Thank you.

Not necessarily Robin.
Light to medium light green leaves is typically good. When the leaves are very dark, like those top ones, that is typically a sign of not enough light. Those diverse leaf colors coupled with the desiccation of the leaves is what led me to the suspicion it was a water based issue.

---------- Post added at 12:06 PM ---------- Previous post was at 12:05 PM ----------

BTW---- have you pulled it to look at the roots lately?

No, I bought it in May and immediately repotted it. It had a spike that bloomed from July-mid September. It seemed like it was drying out a lot so I did a repot in September and added more moss. It’s in a southern window, very bright room, but I was careful not to let it get burned over the summer.

How did the roots look when you repotted? The ideal time to repot is when new growth is starting - which will also produce new roots. Get it into something it likes then leave it alone... frequent repotting disturbs roots each time. I agree with Keysguy, it looks seriously dehydrated... which can be caused either by not watering enough, or bad roots. I would suggest that you water more often - hold it under the faucet, let water run through the pot (which pulls air into the root zone and flushes out crud), then let it drain. Base your watering frequency on conditions in the pot, not the calendar. And as the weather gets colder and you are heating the house (lowering humidity) it's going to dry out faster. Observe, and act according to what is needed.

Oncidium intergenerics shouldn't dry completely. Your plant looks severely water stressed.

Thank you, all. I will definitely water more!