Oncidium Trouble
 

Hello,
I'm new to this forum. And I have a problem with my little oncidium. I can't seem to get new roots to grow. It's a Onc. (Wimpy x Sniffen 'Jennifer Dauro' FCC/AOS) x
Onc. (Mem. Rene Chauvin x Festivale). At first I put it in a little pot, but I'm going to mount it on bark shortly. I'm using a humidifier in my orchid room. I keep that at roughly 55%. I'm thinking this type of orchid need high light. And, I could be doing the most common error, - watering it too much. I'm simply lost at what to do. Please take this link to a pic of oncidium. Thank you so much!
OncidiumTrouble on Flickr - Photo Sharing!

I'm afraid I'm going to lose it.

Hi Heather :)

Oncidiums are not my forte` but here's what I've learned recently and mine are doing much better:

they like high light, they like to be root-bound and they like it moist. Mine are growing in straight aliflor but I was told the growth will kick up a notch if I put them in coconut husk chips, which I plan on doing as soon I have the time.

Let's see what the folks who know more than me have to say about it :)

While I have no Oncidiums, what I know is the whole Oncidium class (more-or-less) likes high light. The photo seems to indicate root rot. The inter-generics I have that are Oncidium class orchids, are in large size bark for lots of air, fertilized and watered 1-2 times per week (depending on growing or not) and in south window. My plants are not in high humidity situation at all - room air which runs dry in winter and a little moist (50%) in summer. Here's my regime (based on Oncidium intergenerics) - Coarse bark, 2-3 times per week watering with 125ppm Nitorgen MSU mix in RO water, full sun south window (when sun shines) supplemented with Compact Florescent bulbs.

Unfortunately, none of those roots appear to be alive... You could try looking up the sphag-and-bag technique that some others have tried, but that never worked for me. I have an Odontioda that I pretty much drowned 7 months ago. It has been BARELY hanging on by sitting over a humidity tray and getting a light misting every morning. I'm pretty sure that while your orchid is recovering you want to give it less light that it would normally like. You don't want it to try and grow leaves instead of roots. Oncidiums have those pseudobulbs so if there is enough moisture in the AIR, it might make it. Humidity is the most important thing in getting some new roots on there. :nod:

yea, I have the same problem with Onc.
I have a habit of overwatering, so now I use zero potting medium in a hanging basket just large enough to hold the plants and give it lots of in-direct light.
With you being in Mich. I would imagine the humidity is the hardest thing to maintain, but the most important.

Once a ps.bulb has reached maturity it usually does not grow new roots, the roots come from new ps.bulbs growths to support those new ps.bulbs. The old ps.bulbs help nourish the new growth until the new ps.bulbs have roots to support themselves. The back bulbs dont need roots, they are done growing. The natural course of an orchids life is to move forward and anything left behind becomes old anchorage.

While we're in very different climates and I grow my Oncidiums on an outdoor screened patio, the biggest challenge in growing them here in Florida has been air circulation. A lot of my intergenerics (Miltassias, and Brassidiums) don't seem to be as sensitive to the lack of a lot of air circulation as my other oncs. but without it, it's almost the kiss of death for them. In my experience, beyond what they're potted in, good light and the fans going, gives them a great start.

In my experience, Oncidiums adapt quickly to mountings. I mounted a few this summer on cork bark with sphag., mist daily (sometimes twice) and the roots and new growth have grown twice as fast since mounting than when I had them in pots.

Happy growing!

Hello everyone- I am new here as well and while I do not have oncidium orchids, I have read as much as possible about all types of orchids. What I have read is any ochids that are actively growing but have few or no roots such as in recent seperation of back bulbs or divisions of plants the best thing to do is let them stay on the drier side to encourage new root growth and when there are more than a few roots growing then you can start watering but still keep them only moist enough to keep the bulbs from shriveling. Once the new roots and newest growth has enough roots to support itself and roots are long enough, you can start back on a normal watering routine.
What I would do in your case, is keep the bulbs dry watering only every 7- 10 days without any kind of media around the bulbs for now and just put them on a mount with wire or mesh around the bulbs to keep them in place. Once the bulbs have thoroughly dried out, then water but lightly so you do not rot the roots anymore than they are. The brown color of the roots in the photo means they have rotted, and plant needs to be kept dry as possible until any new roots have formed and started to grow. After you can see the tips of the roots growing, keep the plant on the dry side and as they grow onto the slab, you may need to water about every 6-8 days.
As the roots grow and attach to the slab, they will need to be watered a bit more frequently but advice is when in doubt keep dry. As you grow the orchid and see how it reacts to your methods, you will find out a schedule that works for watering and feeding but for now keeping it dryer than normal is the best thing to encourage new root growth.
As for light, the best thing is to keep the orchid out of high and direct sun light even if the plant would normally call for it as orchids and plants in general are more sensitive after recovering from root rot or dividing or back bulb divisions. Best thing in my opinion is to keep the plant dry, slightly cooler than normal and more shaded than normal. Those are my recommendations for rehabilitating your oncidium. I once found an oncidium growing wild on a cypress tree and used to tear pieces of it off the tree but eventually there was nothing left and I had no more orchid to collect, but it grew on a bald cypress tree facing north and it was on a tree toward the outer edge of this marsh. The orchid was getting direct sun from mid-day until dusk and was on the upper 2/3rds of the tree- keep that in mind when you have it on a slab and it was dry for the most part.

Did you get that from me, Heather? Tie it to a mount immediately. It certainly looks like you overwatered it. I'd mount it, and set that mount in a clay pot. Back off on the light for a few months.

I don't think it is hopeless though, equitants are tough.

Thanks everyone for the help. I've mounted the orchid. I'll give it a quick spray of water only once a week. And it's out of direct light right now. Hopefully, roots will appear soon...I'll keep you guys posted on progress! Thanks again!