I have been told, and I'm still not certain that this is true...but the Vandas grow thicker roots in drier environments, and that it potentially has NOTHING to do with a microbial association.
Also I wanted to add that photo periods can be very important for spiking and blooming plants. Meaning if it's night for your plants, it should stay night for your plants. They don't have to be in complete darkness, but anything brighter than a dim light for more than a minute or so should probably be avoided unless you are trying to test a plants bloom sensitivity to light. In my experience I've found that Phalaenopsis and Dendrobiums don't care so much about this, and that's one of the reasons why they are so widely cultivated on windowsills. But also I've had Angraecoids and Cattleyas drop blooms in as little as 2 weeks because they got too much light at night. Just something to keep in mind when doing windowsill culture.
I had a new bud on my didieri that I thought was going to be a bloom spike...but it turned out to be another plant. I separated them but haven't taken the one with the keiki off the mount yet...they seem to keep drying out but they also seem alright with that since there are still green tips on the roots...I guess I should put it on treefern like Brooke, though I have some phoenix palm bark I could use. I am asking what is best to use for this plant if I'm not able to water it EVERY day. Any ideas orchid people??
(My Jumellea on the other hand has a spike and a little green flower with a nectary forming

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