Oncidium has a yellow bulb

[Nicola]

Hi, my name is Nicola. I am a relatively new orchid grower / collector. I bought an Oncidium about a month ago (in full bloom). All was going well, but now it has a yellow bulb. I can't seem to find any info on this on the web or any forums. Please help. I want to know if I should repot the orchid, remove the bulb, or leave it as it is.
Thanks

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[ang709]

I would remove the yellow bulbs and repot in a smaller pot with fresh mix.

[Nicola]

And is it ok to do that while it is flowering? Should I repot it in a mix of compost or bark? Sorry for dumb questions. Some books say compost, others bark

[ang709]

The books that say 'compost' are probably using that as a generic term that could mean any type of medium--bark, sphagnum moss, etc. I have my Oncidiums in bark.

General advice says to repot after flowering unless the current potting situation is contributing to the demise of the plant. Others say they have repotted an orchid in bloom with no problem. If it was in full bloom a month ago when you got it, it may be near the end of its blooming cycle anyway. What exactly is it planted in? From the picture it seems the medium may be breaking down.

There are no dumb questions. We are all still learning here too.

[Nicola]

It is potted in pure compost / potting soil. I don't see any bark so I think it might be holding too much water (which common sense tells me is making the bulb yellow)
Yes, flowers are falling off now, so I think it is at the end of flowering. I will repot tomorrow.
Thanks for the advice.

[ang709]

Between the soil, and the fact that the pot looks too big, I think you're right about it holding too much water. It's good you're going to repot.