Vanda refusing to flower

[JambaJungle]

I have about 20 vandaceous hybrids growing outdoors here in south Fl. All but 2 regularly flower every year, a few actually flower 2-3 times a year. I do have two large mature plants which have never flowered. Since they grow side by side with other very similar plants which flower regularly, I am confident it is not my growing conditions. Both plants have massive healthy root systems and grow several inches each year. I purchased both of these plants from growers as local shows. They were "show specials" offered at very low prices for plants of this size. They were large mature plants with extensive root systems. One was well over 3 feet tall with many off shoots(kikis) at the base. The other was a double plant, both growths over 18" tall. This plant had been cut off just 1"-2" from the base and they re-sprouted two twin growths. Each grower had a large supply of these plants they were offering at bargain basement prices. None of the plants had ever shown a sign of flowering. I was assured by both growers the plants would be flowering within the next few months. 3 years later, not a bloom in sight.
It is my belief that both of these growers knew they had stock in a batch of plants that will never flower. These were very large plants, taking up lots of space in their green houses, and never producing a single flower. They dump these plants at shows, offering a great price on a huge plant knowing they will never flower.
I do not know what causes this unwillingness to flower, but I know growers are aware that some plants will just never flower. Years ago, there was a speaker at the Fort Lauderdale Orchid Society who brought up this topic. He has had vandas which just refuse to bloom. His suggestion was to crush the base of the stem with a hammer.... significantly damaging the fibers of the stem, but not destroying them. He claims this shocks the plant into flower. I tried it on one of my plants, and all i got was more kikis around the smashed area!
I would love to hear input from growers on this topic.
The plants in question:
Vanda Manvuvadee x Fuchs Delight: double twin growths, now with several kikis
Vanda tessellata x Aerides lawrencea: now over 4'tall with at least 12 kikis or more.

[charlesf6]

Wow!

[estación seca]

It's certainly possible that individual seedlings might have one or more genetic defects that prevent flowering, while their siblings would flower. The defect could be in a lot of different places on the chromosomes, affecting any of a lot of different enzymes and regulatory proteins involved in flowering.

It would be very interesting to find whether sibling seedlings of your plants (from the same two seed pods in which yours originated) regularly flower. Of course, this would be impossible to track down, since you don't know the origin of your plants.

It is conceivable a certain combination of parent clones containing mutations specific to just those individual parents might yield an entire pod of seeds with mutations preventing the progeny from flowering. But again, it would be hard to track down siblings of your plants.

It is also conceivable a primary intergeneric cross might always yield mules that don't flower. Does anybody know whether any seedlings of Vanda tesselata x Aerides lawrencea have been known to flower?

[JambaJungle]

In both crosses I referred to, each vendor had a large quantity of plants of each cross, all large mature well grown healthy plants, non of which had yet flowered. They were dumping them at a show as a "Show special". I would jump to the conclusion that these were all siblings of the same cross, all refusing to flower, all being dumped to cut the growers loss. In the case of Vanda tesselata x Aerides lawrencea, the vendor was a large Palm Beach County vanda grower who I see regularly at shows. He claims they have flowered this cross......which is suspect to me as when I purchased the plant at the Redlands show a few years back, he had dozens of this cross for sale, all over 3' tall, non of which had flowered.

More importantly, has anyone heard of smashing the bases of the stems to initiate flowering? ......or any other extreme measure to try to force a plant into flower?

[Ben_in_North_FLA]

I believe your suspicions are right on target. I have also grown vandas to ridiculous size and while others around them are blooming, these few just kept on growing. These however, were small seedling purchases. Sounds like you know your way around vanda culture and the old adage is to increase light gradually until you give them as much as they can take without burning (light green NEW leaves). Feed heavy as well (1 TBSP per gallon) weekly or even twice weekly, give them 6 months to bloom or join the compost heap.
Orchid sellers are in business to make money and non blooming plants use expensive greenhouse space that does not generate revenues.... thusly the "show special markdown" to unload these problem plants. Looking for previous blooms on such plants is important and a 3 ft tall vanda that has not bloomed yet and looks like it should have, should go and take up space in someone else's greenhouse. Consider these purchases one of orchid life's lessons.

[Dollythehun]

"More importantly, has anyone heard of smashing the bases of the stems to initiate flowering? ......or any other extreme measure to try to force a plant into flower?"

I've heard of similar abuse among other plants: crushing hostas to develope the dormant eyes; severe pruning to develope fruit or flowers. So, the concept us not unheard of.