Sick orchid - leaves turned yellow and dropped off after re-potting

[lemonslice27]

Hi everyone,

I recently re-potted an orchid which was doing well. The next couple days 4 to 5 of its leaves turned yellow and eventually fell off. I attached a picture where it only has two big leaves left; the yellow one fell shortly afterwards. Does anyone know what might have caused this to happen? Could something have gone wrong with my orchid mix? Should I toss it out? And how could I encourage this orchid to grow more leaves back / stay healthy?

Thanks!

[Roberta]

What was the condition of the roots when you repotted it? Also, did it perhaps get a chill when you were working with it? Or did you do any sort of "treatment" when you repotted (if you used hydrogen peroxide, you could have killed roots...) Does that pot have good drainage? The bark looks a bit on the large side, but if you keep the plant adequately watered that can be beneficial. The one good leaf looks OK and the crown of the plant (the little pocket at the base of the leaf) looks like it might be starting a new leaf. If so, it will recover nicely.

[lemonslice27]

The roots were in good condition when I re-potted it and I didn't give it any kind of temperature changes or treatment. I also had another orchid whose pot I topped off with more bark and it had a couple leaves turn yellow and drop off as well that I should've mentioned. That's what makes me think maybe I introduced an infection somehow when re-potting (perhaps my hands weren't completely clean or something managed to get into the bark?). The other orchids I have that weren't introduced to more new bark seem fine. Would you suggest caring for it as I usually would? I'm really hoping it does recover I'm glad it managed to hold on to that top leaf.

[Roberta]

Originally Posted by lemonslice27

The roots were in good condition when I re-potted it and I didn't give it any kind of temperature changes or treatment. I also had another orchid whose pot I topped off with more bark and it had a couple leaves turn yellow and drop off as well that I should've mentioned. That's what makes me think maybe I introduced an infection somehow when re-potting (perhaps my hands weren't completely clean or something managed to get into the bark?). The other orchids I have that weren't introduced to more new bark seem fine. Would you suggest caring for it as I usually would? I'm really hoping it does recover I'm glad it managed to hold on to that top leaf.

Hmmm... maybe there IS something in that batch of bark (I can't think what would be so drastic in its effect) I think care for the plant as you do your others. If there is some sort of chemical "bad actor" in the bark, maybe change it out with bark from a different source, and flush the medium well.

[lemonslice27]

I'll try that! Thank you.

[SouthPark]

lemonslice - Roberta also asked what sort of pot you use ---- and asked if it has good drainage.

Good drainage (enough holes on the bottom of it) is good for the plant. It allows water to drain right out, and also allows air to flow through the pot - provided that the media is airy enough to allow for good air-flow. Good air-flow across the roots and through the media in the pot is beneficial to the health of the plant.

So - to give the orchids growing conditions:

1. good drainage pot (maybe with a grate or stand so that the bottom of the pot doesn't get the holes blocked by whatever the pot rests on).

2. airy media that doesn't become water logged, but allows some moisture to be retained during watering ..... eg. scoria or bark pieces ------ but the bark pieces need to be suitable for orchids - not ones that might contain chemicals or compounds that could kill an orchid. Eg. a lot of growers use 'Orchiata bark'. The choice of media size needs to match the size of the roots. If the pieces are too small - waterlogging can occur. Too large, and the roots might not get enough contact with the media, and the plant dehydrates and dies slowly.

3. comfortable temperature for the orchid - should be maintained.

4. suitable light level and duration are required.

5. good air-flow around the whole plant (leaves, stem, roots, media) ----- avoid still-air growing environments. Still-air invites certain unwanted issues - certain unwanted fungus, and can also get in the way of good water/oxygen movement through the pot across the roots and media.

In your case - maybe your pot is not good draining. And maybe you haven't had good air-flow (eg. movement of air by breeze and/or fan). Or - as Roberta mentioned - that particular type of bark may be poisoning the orchid.

Another thing is - dry bark won't easily get wet unless it's being bombed by water for a relatively long time. Water runs straight off dry bark, as very dry bark repels water. So this needs to be considered. If the pot stays 'light' after watering - it can mean that the bark hardly absorbed any water. If this happens - the plant won't get much or any water into it, and can die slow - as in yellowing leaves, and dropping leaves.