New problems after 2 years in SH
 

I saw Nanella's post about her success with Oncidiums in SH culture. I too have had success with the same variety planted in SH.

Recently though I've experienced some problems with one of my plants. She's a dancing lady type that has been growing in a 7" pot for 2 years. She's grown well and is almost always in flower. About 4 weeks ago I noticed 5 new spikes emerging and then the leaves from her newest growths began to show signs of dryness (accordion folds). Upon closer examination I could see that the newest pseudobulbs were growing upwards on top of mature growths instead of around the edges. They were stacking on top of one another and I concluded their roots were not being supplied with an adequate amount of moisture. To remedy this I sprinkled some more SH pellets between the growths. I've been misting these surface pellets because they do not come in direct contact with ones in the pot. Therefore they cannot wick. I've been careful to not mist the leaves. During this time the leaves from new growth had begun yellowing from the tips. I've clipped off the yellowed tips to determine if this was a temporary situation due to a former lack of moisture or ongoing due to still existent moisture problems. The yellowing has continued to travel backwards from the cuts.

Today, I removed the plant from the pot and checked out the roots. The roots from prior growth seemed to be happy. The were no fresh green roots (from new growth) penetrating the potted pellets. The stacking growth habit of the newer pseudobulbs seems to be the problem.

It's a challenge to keep moisture at the base of the new growth when they're growing 2 or 3 inches above the pot. I also fear that stacking pellets in the crevices will cause the older deeply seated pseudobulbs to rot. I'm not complaining about SH because the plant has been thriving. This was my first Oncidium purchase. It's gotten large and the growth pattern seems to be evolving with age. The stacked growth habit could be natural for mature plants. I really don't know.

Has anyone else experienced this problem and does anyone have suggestions as to how to resolve it? If I divide the plant it will still have stacked growth so I don't know what to do. Is it normal for mature Oncidiums to begin stacking their pseudobulbs? I just feel the need to put something moist around the base of the newer growths but I don't know what to use. The SH pellets are round so they tend to get displaced when I move the plant. After examining the rootsI cleaned the algae from inside of the pot and planted the Oncidium a little deeper. There wasn't much room to play with. Are SH pots available in sizes larger the 7 or 7.5 inches?

I just took a similar onc out of s/h for the same reason. It literally climbed out of the pot.

I wonder if part of the problem is due to pot size. Some sides are filled to the edge with growth but there are some areas that are vacant. The newest pseudos are larger than ever and maybe the plant senses that the space is too tight. If I continue SH I'll have to make do with a flat bottomed storage container or the top of a plastic cake keeper turned upside down. I'm hesitant to transition to regular media for fear of a potential death sentence.

How did you transition yours and did you fill the voids to supplement moisture?

It looks like it could easily be separated into two or even four plants! That maight help with your problem...

The new grow sounds like classic symptoms of lack of adequate moisture. The quick fix is to water more frequently hosing the whole plant down in the morning so it has time to dry during the day.

I think it's time to divide and repot. If you don't want to divide the original plant, you might want to try carefully teasing the newer pseudobilbs and roots out potting them up separately and moving the main plant into a bigger pot.

Cheers.
Jim

I'm not so sure this one could be easily separated. The new growths that need to be in the medium are stacking one on top of the other. I'd have to remove the uppermost growths individually and this would not be good. The lower growth is seated in SH and the roots are tightly wrapped around the pellets so I'm not sure how to approach a division from this aspect either. The only suggestions I've seen for repotting SH is to just transfer the root/pellet mass into a larger pot and then add more pellets. This looks easy enough but it still doesn't address the issue of providing moisture for the stacked growths.

It must be difficult to divide Oncidiums because there are very few threads that address the division process. I divided an organically grown overgrown Burr. last summer and it was a bear to deal with. I tried to preserve the integrity of the pseudobulbs and wound up with 3 strange looking semi-circular divisions. All managed to survive and produce new growths but they look weird and haven't initiated spikes.

Perhaps its better to make a clean, firm downward slice at one point through all the pseudobulbs. The damaged bulbs would certainly perish but this method would maintain the clustered effect of the surviving bulbs. I still can't figure out how to divide the roots that are tightly wrapped around the SH pellets without inflicting severe trauma. I haven't seen topics addressing SH and division. It would be enlightening to know how this is done.

On Rays site, he just pots up the whole mass into a larger pot without disturbing the existing root/pellet mass. Just as you would with a houseplant in soil.

Cheers.
Jim

I know repotting is easy but what do you do when the plant gets too large and needs to be divided? How do you safely divide a SH grown plant and what is the correct way to divide an Oncidium. These are the two topics I'd like to address and perhaps they should be in different forum topics. There is very little information out there regarding these two subjects. Most of the available SH information addresses the how to's of conversion, watering/fertilizing info., and success/failure stories. I'm past that phase and have successfully grown in SH. My plant is large (growing in a 7" pot) and trying to get larger. Honestly it wouldn't be practical to keep upgrading the plant into larger containers. Pretty soon you wouldn't be able to lift the thing and who has the space (for example) for 100 oversized SH grown plants or the money for a truck load of pellets?

I think it's time with all the great success stories to address the issues involved in SH division. Plants that are are happily growing in SH are going to just keep getting bigger and bigger. There comes a time when you have to stop the madness. Did you see the movie "Little Shop of Horrors"? :shock:

From what I've read in other threads, the upward growth is classic for Oncidiums. My Sharry Baby is doing it also.

As for repotting, the few times I've tried it with an Onc were difficult because of the tangled root mass and ended up being more of a hack-and-slash scenario than an artful division of pseudobulbs. They survived though.

This issue is a nature of the plant, totally unrelated to S/H culture.