Limp Leaf Oncidium - Orchid Board

PantherBinx · #1 02-25-2020, 12:10 PM

This is my first Oncidium that I received for Christmas and I feel like I am failing this plant already. I’ve been watering weekly. Idk I’m at a loss. I’m fighting a mealy bug infestation from bad bark. And I really don’t wanna lose this kid.

neophyte · #2 02-25-2020, 12:20 PM

Hello PantherBinx, the issue is that your Oncidium is not taking up nearly enough water. You can monitor dehydration by observing the pseudobulbs – currently they are almost flat (they should be plump and round). Considering that your Oncidium is in a fairly large grade bark mix, watering once a week is most likely not enough because bark drains and dries very easily. Also, the plant is still small, so its root system is probably not so extensive, and more frequent watering will probably be beneficial. It doesn't seem like the bark is breaking down, which is good, but if it is, then the root system might be rotting and that would also lead to dehydration (but that doesn't seem to be the issue). Good luck – I'm sure your plant can recover!

WaterWitchin · #3 02-25-2020, 12:34 PM

I second that opinion! More water! Do you have it in an outer pot with no holes? Or does it just sit like that in the slotted pot? It might help to get an outer pot with no holes to put it in so it retains moisture a bit more. I doubt the humidity is high enough, but watering more is your quickest need to take care of.

SouthPark · #4 02-25-2020, 05:45 PM

Totally agree with neo and ww ---- with that relatively large size bark pieces - any new dry bark (or any bark that gets quite dry) will actually repel water. So watering dry bark will be like water running off a duck's back. The water might not get into the bark much at all. This means - make sure that you know the weight of the pot (roughly) for dry bark. And then know the feel of the pot when there's water absorbed by the bark - which is going to be a heavier pot.

Also - was this orchid always potted in that large slotted pot? I see signs of leaf rotting or something. So that might be another issue too. If the orchid was previously growing in a different pot with conditions that allowed for root rotting issues (too watery media, and not good enough drainage, and still-air environment etc), then issues could have arisen from there. But that's just a maybe.

So, aside from more watering of this media needed (for the existing pot) - some application for stopping rot might be needed too --- that's if there are signs of leaf rot. Maybe spray of agri-fos onto the whole plant.

If you have mealybugs - then maybe a spray of imidacloprid onto the plant (leaves, stem, roots and all) will control them.

The orchid is very dehydrated right now, and possible rot on leaves.

Put it in a warm place, and avoid still-air growing conditions, and provide medium light levels - no direct sun.

aliceinwl · #5 02-26-2020, 03:13 AM

If you’re having trouble gauging moisture by weight checking out the sticky about using skewers to monitor water levels in the Beginner forum might help. If the bark seems like it’s not taking up water, you might consider letting the pot soak for at least five minutes then allow the water to drain out.

If the roots are very superficial or mostly dead, you may also want to consider a heavy daily misting of the base of the pseudobulbs only. When I’ve had Oncidiums with dead-mostly dead roots, I found this worked to keep the plants hydrated until they could send new roots into the substrate.

You may also want to check your temperatures. In my experience the leaves sometimes start looking like yours if the plant has been kept too cool for an extended period. You should probably avoid lows below 70 degrees Fahrenheit if you can.

Good luck!