shrunken pseudobulbs on Oncidium types

[mrspiza]

Hi, everyone.

It doesn't seem to matter what I do, but I just can't grow anything in the Oncidium alliance. (At least, I think they are.....I'm talking Brassia, Miltassia, Burrageara, etc.) It never fails....it's beautiful at the grenhouse, and within a week of being at my house, the pseudobulbs shrivel and the plant goes into a slow decline. At first I thought it was because I was overwatering, so I tried again and cut back. The new ones shrivel anyway, so I'm at a loss. I realize that the humidity in my house is much less in the winter than the greenhouse, but it's very high in the summer months and I have the same problem with new Oncidiums then. I have no problem growing many "more difficult" orchids, like Phalaenopsis bellina, Psychopsis, Epidendrum, Maxillaria, and Zygopetalum. I keep reading that Oncidiums are supposed to be some of the easiest orchids, and often suggested for beginners, but that's definitely not by experience thusfar. Please, help me overcome aversion to these beautiful plants! Any suggestions would be appreciated. Thanks!

[amersault]

hey, there!

i, too, find Onc's challenging and contrary to what's been said, i've sent a few to Orchid Heaven a bit prematurely.

i think it largely all depends on the type of Onc you have: some Oncs tolerate a warm/intermediate temp range, while others fall in the cooler growing spectrum and cannot withstand temps over 75 indoors. it all depends on what type of plant you are dealing with.

here's what works for me in my environment:

to combat PSB shrivelling, i've added saucers/bowls under each plant and hardly ever let that dry out. my key to watering will be when the saucer is near empty and the water is low. PSB shrivelling can also indicate too much light in combination w/ the drying out prcoess, so you need to be mindful of light intensity on your plant.

i've noticed my Brassia benefitted from a transfer to all-sphag medium, while the others resented this and were returned to bark; same rules of saucers and constant humidity apply.

i also make sure to cool these plants at night and by cool i mean a 10+ degree temp drop. it's the only way my cool-growing Ocda Lovely Penguin Emperor survived this long w/ no PSB shrivelling.

i hope this helps somewhat.

[mrspiza]

So mean in a saucer of water like some do with Phragmipediums? My gut say they'd rot, but hey, I'm willing to try about anything at this point.

[jerrymeola]

It sounds like you are growing them too dry. Oncidium can take a lot of water especially the Intergeneric you listed.

Amersault's technique eliminates this possibility in his plants.

What seems to be happening is the medium dries out before the plant can absorb enough water and goes into slow decline. This may be starting in your greenhouse and accelerate when moved into the house.

If you meant it was beautiful in a sellers greenhouse and declines in your home, I would raise the possibility to 90 percent that you are not watering enough.

This is accelerated if the plant is in bloom. The flowers take their nutrients from the pseudobulbs, not directly from the roots. You need to water long enough for the plant to drink heavily.

[amersault]

Originally Posted by mrspiza

So mean in a saucer of water like some do with Phragmipediums? My gut say they'd rot, but hey, I'm willing to try about anything at this point.

i don't have any Phrags, but yes - a saucer under your Oncs kept constantly wet works. let water touch the bottom of the pot. to up the humidity, add pebbles to the saucer/bowl you are using so there is some moisture in the air due to evaporation.

what Jerry mentioned is also true that the plants may not be getting enough to drink. in my environment, in the summer, everyone w/ a PSB gets a sip daily. that's to avoid PSB shrivelling in the summer months. in the winter you can adjust watering accordingly, but i find i keep refilling the saucer due to the dry air.

again, it largely all depends on what type of Onc you have but that's what's worked for me so far

[CharliesAngel51]

I'm Certainly no expert but I have a Den. that is planted in a very small pot with coarse bark. When I watered it the water just ran through. After it had lost two leaves I asked for help. Someone on the board suggested that instead of watering from the top that I let it soak in water. Now I put it in a clean container and fill the container until the water seeps up to the top of the bark in my pot. I let this sit for about 20 min. That gives the roots and the bark time to soak up the water. I have been doing this about once a week and my Den seems happy. No more lost leaves.

[mrspiza]

Hmmmm, perhaps I will have to go buy some saucers. I have all my orchids on humidity trays. Another question...what media do others use? I've tried sphagnum (too wet...plants rotted), fine fir (Paph mix), and large fir (Phal mix) without much success. My Maxillaria tenuifolia has nice plump pseudobulbs, and I have it planted in fine fir bark, so maybe that's the route I should take.

[amersault]

all the ones i have came planted in fine bark, or coco husk. w/ the exception of Onc. Rosy Sunset that came in sphag and thrives in sphag. the cooler growing types benefit from the live moss that dress the surface mix. the Brassia was orginally in lavarock and was very unhappy; i made a leap to try sphag and my original PSB shrivelling problem disappeared.

saucers vs bowls: i hit up thriftstores and get them for $0.50 or less. huge array and fun to go through, but anywhere is good, too

[janet_a]

the only way i can keep them alive is in semi hydro. they're not lovely, but they're alive.

[grandmapenguin]

Originally Posted by amersault

hey, there!

i, too, find Onc's challenging and contrary to what's been said, i've sent a few to Orchid Heaven a bit prematurely.

i think it largely all depends on the type of Onc you have: some Oncs tolerate a warm/intermediate temp range, while others fall in the cooler growing spectrum and cannot withstand temps over 75 indoors. it all depends on what type of plant you are dealing with.

here's what works for me in my environment:

to combat PSB shrivelling, i've added saucers/bowls under each plant and hardly ever let that dry out. my key to watering will be when the saucer is near empty and the water is low. PSB shrivelling can also indicate too much light in combination w/ the drying out prcoess, so you need to be mindful of light intensity on your plant.

i've noticed my Brassia benefitted from a transfer to all-sphag medium, while the others resented this and were returned to bark; same rules of saucers and constant humidity apply.

i also make sure to cool these plants at night and by cool i mean a 10+ degree temp drop. it's the only way my cool-growing Ocda Lovely Penguin Emperor survived this long w/ no PSB shrivelling.

i hope this helps somewhat.

This may sound like a dumb question but how do you drop the temperature 10 degrees at night

[mrspiza]

At my house, the temperature drops at night for a couple reasons. First, we turn the thermostat down about 10°F before we go to bed all year, and secondly, we stop putting logs on our downstairs fire during the winter, so the lower level drops even more in temperature. I'd guess our lower level is about 68°F during the day and 55°F at night. Besides saving energy and money, lowering the thermostat at night makes for happier orchids and more comfortable sleeping conditions, in my opinion!

[articuno75]

Originally Posted by mrspiza

Hmmmm, perhaps I will have to go buy some saucers. I have all my orchids on humidity trays. Another question...what media do others use? I've tried sphagnum (too wet...plants rotted), fine fir (Paph mix), and large fir (Phal mix) without much success. My Maxillaria tenuifolia has nice plump pseudobulbs, and I have it planted in fine fir bark, so maybe that's the route I should take.

I grow many Oncidiums and I don't use saucers at all. The trick to my growing is that I mist the base of the plants and medium daily. Every 4-5 days I give them a good long watering.

Oncidiums are very thirsty drinkers, yet they don't like to have roots that are constantly wet. I use cocohusk, charcoal and a little bit of perlite and hydroton for my medium. This mix stays wet long enough for the plant to drink, yet dries out fast enough right before the next watering.

In winter my apartment is more arid so I do have to mist more often doing so twice daily. I have a couple of Oncidiums that are growing like gangbusters and as I said before in a couple of other threads my Psychopsis has another spike that is shooting for the moon.

[kid a]

I have issues with psuedobulbs shriveling too on these types. My two newest plants I won from the society raffle look really bad and they were so beautiful when I got them. ALmost anything with psuedobulbs presents a challenge for me except for my project encyclia, lol.

[digitalgate]

You got to discover what works for you. I have problem growing Oncidium Gold shower in the beginning!!! They just keep dying on me. Until i mount them to trees then they do well.
To some people sphag moss, to some wood chips, to some charcoal, to some fern bark.
some people brick, granite chip... It is difficult to tell you a good answer to your question. I growing my Golden shower var codwell in sphag moss in my weather. It has a double spike right now. So what good for you. I don't know.

[lmartiny]

I stay confused. I'd read oncidiums are easy. I've got a big one (I think) that has hung pretty ignored outside. It has grown and put out a spike last summer. I've now learned I repotted to a too large basket and think that is why it did not flower for 3-4 years. I have trouble keeping up with what's what.
I've considered little sign tags. "I'm a _____, water me _____, fertilize me _____ and I need ____ amount of light." If they still fail, well. then, "blankety blank....." Keep trying.

[amersault]

Originally Posted by grandmapenguin

This may sound like a dumb question but how do you drop the temperature 10 degrees at night

in the summer or on warmer days, i confine everyone to one area and crack open a window. the breeze alone cools the entire/room area by easily 10 degrees no matter how the heater kicks in.

during winter, all i have to do is move some of the plants closer to a windowpane. the cold air outside creates a micro-climate against that glass that also cools the immediate area inside the house. i use the same trick to get all my Phals to spike on time