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?