How to get an Oncidium to grow psuedo bulbs? - Orchid Board

greenpassion · #1 09-12-2013, 04:30 PM

I have had several oncidiums for some time now, none of which spiked until recently. In studying them, I (duh) figured out that the spikes come up from the sides of the pbulbs. So, I began wondering-if I could get more pbulbs on these, I'd get more spikes. Right? I have focused mainly on my phals, and an odontoglossium noid, which does not have bulbs but has sent up 2 to 3 spikes and bloomed for me at least 2 times a year. I have an Onc. that was given to me like 2 or 3 years ago, and never spiked-until now. It has 3 or more bulbs, but the one spike is coming from what appears to be an new bulb, nice and plump, as the others, that were there when I got it, are rather wrinkled. It's grown in S/H, using RO water, and recently it's been fed Ray's food specifically for RO watering. I think it was starving, and now, well, we'll see. Any way, how do I get Oncs to grow more bulbs?

Bud · #2 09-12-2013, 04:34 PM

They have very tiny sensitive roots and sometimes they sulk if you disturb them badly....just be patient and give it the proper culture; these kind of plants will grow like grass when they get used to your environment....

tucker85 · #3 09-12-2013, 04:54 PM

If you're growing in natural light it probably won't grow new pseudo-bulbs until spring, when the days start getting longer. If you're growing under artificial lights, I guess you could get growth at any time. I've never grown that way. How many new growths you get is mostly controlled by the DNA of the orchid. Some orchids will grow lots of new growths while others, by their nature, will only grow one or two.

WhiteRabbit · #4 09-12-2013, 06:53 PM

They start new growth when ready, and as many as the plant can support reasonably. Some, when rather mature may seem to always have new growth on them. The bigger the plant, the more new growths it can have. A small plant may get only one or two a year until more mature.

I suppose that cutting notches in the rhizome may cause a plant to start more new growths than it might have otherwise, but if the plant is of smaller size, these extra new growths may be undersized and bloom poorly, if at all.

terracotta7 · #5 09-13-2013, 09:16 AM

I am by no means an expert, but I do have these orchids and they do very well for me. My first was given to me for Christmas by my son. It had one spike which bloomed for quite a while and then it grew and grew the following year and I had to divide it. Those two plants each made a spike from their new pbs the following year. This year those same plants are getting top heavy in their pots and they each have two spikes, one coming from each of the pbs that they made this year. After they flower, I will have to repot them and probably divide as well.

Here is the thing I wanted to say, though: I am learning that when you repot you have to get those older pbs on the edge of the pot and put the newer ones towards the center so that they have room to put out the new growth. This is something that I think will come with experience for me...but right now I am happy as can be with what I am seeing: new spikes everywhere! My Nelly Isler Burr. has three!!!! Cannot wait to see that blooming again!

Good luck and keep us posted on your progress!

greenpassion · #6 09-13-2013, 09:51 AM

Thanks to you all for your responses. Now, here's another question regarding these pbulbs. Why do some look like the leaves have been clipped off the top of the bulbs? Every onc. I've ever seen have these pbulbs with chopped off tops. Does the plant do this naturally? Or are the leaves supposed to be cut off the bulbs at some point?

WhiteRabbit · #7 09-13-2013, 08:14 PM

Pbulbs absent of foliage? Or foliage with the ends cut off?

Pbulbs without leaves are probably old ones that have shed their foliage. Leaves with cut off tips/ends were likely browned or spotted, and that part was cut off to make the plant look nicer.

Also, the bract foliage - the leaves that envelope the developing growth / pbulbs - will die off and separate at a distinct line.

greenpassion · #8 09-14-2013, 09:19 AM

Actually the bulbs seem to have the leaves that grow out of the top cut off. Right at the top of the bulbs. I know about trimming the ends of leaves to cut off damage or diseased areas, but this is not leaves, it's the oval bulb with the growth that comes out of the top cut right off. ??

Leafmite · #9 09-14-2013, 11:50 AM

Do you have a picture? The p-bulbs do stay green sometimes after they have shed leaves. That is quite normal. But if these oncidiums are new, perhaps someone removed the leaves prematurely to make the orchid more presentable for sale...perfectly normal, too. Oncidiums often get these darn little spots and brown leaf tips that are rather unsightly.
I find that once oncidiums are established they grow very, very well.

---------- Post added at 11:50 AM ---------- Previous post was at 11:44 AM ----------

Terracotta7, I hope you will post pictures when yours is in bloom! Last winter, I gave away my nice, large, established Nelly Isler because it was Christmas and someone was admiring it. I started over with a new one and it was so small and took forever to get established! I miss those gorgeous blooms!

terracotta7 · #10 09-14-2013, 02:34 PM

Greenpassion...my oncidiums have the same thing on some of the oldest pbs. I think they might be called backbulbs, but I am not sure. If that is what they are, I think that I read somewhere that you can remove these and pot them up and, if you are patient, you might get another plant. Please look this up, because I am just a beginner and I have a lot to learn. Perhaps you could do a search here on OB for "backbulbs" and see what you can find out. Someone might even have a picture that you could compare your orchid to.

Leafmite...I will definitely share pics when it blooms. My husband will have to help me because I am not a tech savvy person. Believe me I am so excited to see these blooms!!!