Oncidium type ID and suggestions

[Vivienne]

Hi everyone!

About a month ago I picked up 2 little oncidium (?). No tags, of course, and they are my firsts. My Orchid book lists several different types of oncidium - I'm a bit confused. So here are all my questions.

Is this an oncidium? If so, what type (equitant, hard round pbulbs, tender pbulbs, mule-eared, etc)?
Don't really care about a name, but if you have one great!
How much light do they need?

I'm alternating damp and dry phases for water. Most of the pbulbs (referring to both plants) are smooth but a few on each plant are dimpled,withered, not smooth. Causes? Cures? Normal?

Both are in 3" pots, one rather crowded, the other with a tiny bit more room. The pics are of the crowded one.
Should this be repotted? Divided? Could they both be potted together? When to repot? Do they do well mounted?

Any and all suggestions and responses are welcomed. Of course, the big question is exactly what am I dealing with? I can research the rest after that perhaps.

[prisana]

Hi Vivienne,

My knowledge in onc. is limited , but I do know that you have a mini/compact onc. The smoother pbulbs are probably the newer ones, as the older ones usually show some signs of slight shrinkage and that's normal. Some onc. like to be pot bound especially the equitant ones ( the equitant's leaves grow out like fans and you almost can't see the bulbs themselves ) so your's isn't an equitant. It doesn't look like the mule's ear type either.

My personal opinion is that keeping the plant in one speciman size is more beautiful, but you can divide it if you want and even remove some old leaveless backbulbs and stick them in a bag with we sphag and seal it, you might get some tiny plants growing out of the old bulbs in a few months that way.

Sorry I couldn't help more..hope someone else can do a better job in giving you a more specific care and id.

It's a beautiful plant, by the way.

[prisana]

Oh, same general rule applies to division, at least 3 bulbs in one division. I would wait to repot after the blooms are finished and they are great mounted, just have to remember to give it a big enough room on the mounted slab of your choice, they grow upward on the mount. Good luck

[Vivienne]

Thanks for your insight prisana. Since I have 2, I may repot the crowded one to a 1" larger pot and divide the other. It's ultimately going to hinge on what their light level needs are. If it's lower light then I could put them all in one larger pot. Higher light and I'll need to get creative somehow.

[prisana]

Vivianne,
Ultimately it all comes down to what you think is best in your growing condition..and like they say..." mother knows best "..

[kmarch]

It looks like either the species ornithorhynchum or perhaps it's most famous hybrid Onc. Twinkle. I'd have to take a close look to be sure but my bet is Onc. Twinkle which is more commonly found. Is it fragrant?

You have a beautiful healthy clump of bulbs that will put out multiple spikes every year with good care. Don't divide it. If it is getting too big for the pot, repot into a slightly larger pot, only enough for about 2 years' worth of growth and let it continue on and get bigger. The bigger the plant the more flowers you will have. Fortunately because of the compact plant habit, this plant can get "enormous" and still be a managable size. These (if it is indeed Twinkle) were bred to make showy specimen plants. i sometimes see Oncidiums mounted but usually see them pot grown.

As everyone probably knows I am not a fan of dividing plants unless there is a compelling reason (disease or decline). As orchids grow into bigger and bigger specemin plants they reach what i like to call "Critical Mass," the point at which all of a sudden the plant starts blooming bigger and better. It has to do with the plant finally getting big enough and strong enough to really go into high gear blooming. Let this little guy grow on and every year you will have a show more spectacular than the last. I've seen clumps of Onc Twinkle that had probably close to 500 little flowers on it. They're spectacular.

Go to www.aos.org to get a good Oncidium culture sheet.

Equitant Oncidiums (which are now all properly called Tolumnia) look very different that "regular" Oncidiums. The don't have big pseudobulbs. They have small-ish fans of very stiff pointed leaves. I usually see Tolumnias grown mounted. They will interbreed with Onc though and are often used to impart red colours.

[Vivienne]

thanks kevin. I think I'm set on repotting and not dividing. Since I have 2 exact plants would it be okay to put them together or keep them seperate?

It is slightly fragrant... something I didn't notice earlier. Perhaps fragrant in the evenings. Was doing some googling and found an Onc. Twinkle 'Fantasy Fragrance' which looks very much like mine.

[PhalPal]

I thought I would bump this thread because I have ventured into the world of Oncidiums and have lots of questions.

'Equitant' and 'Tolumnia' confuse me; I cannot find exacting definitions. Are they synonymous terms? I have 24 orchid books now and I can't believe how often I can't get my answers!! That's where you guys come in.

My understanding of equitant is tiny flowers? like Onc Twinkle?? Does Tolumnia = equitant/miniature oncidium??

Also, what do you pot your Oncidiums in?? I bought on from SBOE and it was potted in large coco husks and perlite but that doesn't seem to be working well for me now. Any suggestions??

[articuno75]

Also, what do you pot your Oncidiums in?? I bought on from SBOE and it was potted in large coco husks and perlite but that doesn't seem to be working well for me now. Any suggestions??

Being the thirsty boogers that these are, you might have to water or mist them more frequently. Are you getting the "accordian" effect? Gotta love Spagh.

[Tobi]

Connie,
My personal rule of thumb is the larger flowering Oncidiums, I use a medium grade
bark. The smaller ones like Twinkle and ornithorhynchum, I go down to a smaller grade.
I use charcoal to sweeten and absorb the acids. Several growers I know also use larva
rock to aerate the medium as well. The main thing is to make sure the fine roots have
enough air to dry almost completely between waterings. Good air flow is the most
important factor in assuring they are getting the best cultural environment.

[PhalPal]

Thanks for the input everyone. I have a few accordian leaves on a smaller leaved oncidium but not on the larger ones. They are in a very airy mix and I was thinking maybe too airy??
Jenny you grow yours in spraghum and they do okay???

[articuno75]

Chopped Spagh and charcoal/bark mix, more Spagh though. They do fine. It depends on how dry your air is. The Spagh is cut in 2-3 inch strands, mixed in coal/bark. I still have to mist everyday and I water every 4-5 days.

[phalaephila]

PhalPal:

I'll try to help you with the Tolumnia/equitant question. There are a group of species, previously in the genus Oncidium, which have thicker, stiff leaves. These leaves, if cut to make a cross-section, are triangular in shape, thus the term 'equitant'. Recently, taxonomists have reassigned these orchids to the genus Tolumnia. Here's a link with information:

Equiatnt Oncidium or Tolumnia Orchids

Hope this helps!

jeanne

[PhalPal]

Great link Jeanne - Thanks!

I have a few orchids, well, SIX, ordered from Oak Hill Farms and one of them is 'Equitant' and one is 'Tolumnia.' Then there is the 'Potinara'..????... good heavens lets just call it a mini catt! I'll post pictures of my new babies when I get them. Some are mounted and all but one will be pretty small. The little Catt is gorgeous!! I can't wait to get them; I couldn't hold out until the orchid shows start around here beginning of February.

[kmarch]

Originally Posted by PhalPal

...one of them is 'Equitant' and one is 'Tolumnia.' Then there is the 'Potinara'..????... good heavens lets just call it a mini catt!

It sounds like we might be confusing some of our names here. Please forgive me if I say things you already know, but for the sake of those who don't know these things:

Equitant oncidiums and tolumnia are the same thing. When they were still members of the genus Oncidium, they were called "equitant oncidiums" to distinguish them from other oncidiums. This group of oncidiums have been split off from the rest of the oncidiums an d given a different generic name. The generic name for these plants is now tolumnia.

It sounds as if we're confusing generic names of orchids (e.g. tolumnia, potinara) with the name for broad general kinds or types of orchids (e.g. mini-catts). There are many different genera, all of which are "mini-catts." Mini-catts can be Lc., C., Sl., Slc., Potinara, etc., etc. To simply call them all "mini-catts" is a bit of an over generalization, especially since some Potinara (for example) are not mini-catts.

A potinara could be a mini-catt depending on it's parents, but Tolumnia are not mini-catts. They are a completely different genus and will not breed with cattleyas.

[PhalPal]

Originally Posted by PhalPal

'Equitant' and 'Tolumnia' confuse me; I cannot find exacting definitions. Are they synonymous terms? My understanding of equitant is tiny flowers? like Onc Twinkle?? Does Tolumnia = equitant/miniature oncidium??

Thanks for answering my question Kevin about Equitant/Tolumnia being synonymous terms. I don't understand why the same grower will call some orchids Equitant and some Tolumnia if they mean the same thing.

SO! Tolumnia = Equitant = Miniature Oncidum?? All synonymous and interchangable, correct? We will see what I actually get and how it is labeled and go from there.

[kmarch]

Originally Posted by PhalPal

SO! Tolumnia = Equitant = Miniature Oncidum?? All synonymous and interchangable, correct?

Almost. Tolumnia = Equitant Oncidium. These are all now officially properly called Tolumnia. That is the recognized genus for this group of plants. Why different growers/nurseries say one or the other, I can't say....maybe it's just laziness, I'm not sure.

I never use the term "miniature oncidium" for precisely the reason we're havign to explain tese things, because people get confused by the term. There are various species of Oncidiums and some hybrids too, which are still properly called oncidium, which are small. So not all miniatures are Tolumnia. My question is why bother using the term "miniature oncidium" at all when people are confused by it. Why not just call them by their proper names?