Using lava rock to pot all my orchids.

[Leafmite]

I believe that the main reasons most people fail with lava rock is:
1 Failure to flush the rock very well to get rid of unused fertilizer and fertilizer residue. This is so important since one is not changing out the medium every year as they are with bark or moss.
2 Not watering correctly.
3 Forgetting that the rock doesn't contribute significantly nutritionally to the plant.
4 Using too strong of a fertilizer when the orchid is kept too dry
5 Thinking that all orchids need the same care. It can be impractical to grow some orchids in lava rock. i.e. for me, these are: Phaius, Vanilla, tiny miniatures that prefer being mounted, Bulbos and the Pleuro that need constant moisture

[SouthPark]

Originally Posted by Leafmite

5 Thinking that all orchids need the same care. It can be impractical to grow some orchids in lava rock. i.e. for me, these are: Phaius, Vanilla, tiny miniatures that prefer being mounted, Bulbos and the Pleuro that need constant moisture

This is absolutely true (as with all those other great points you made) LM.

For vanilla, it can indeed be impractical in certain regions, or even various regions. In some places, like in my region, the humidity is generally pretty good and high enough to sustain the vanilla orchids. So my vanilla orchids grow just fine in scoria ----- which do get some water from the scoria, but also grabs a lot of water from the air through their tendril-like roots.

I'm thinking that in dry places, the vanilla orchid can get long, and possibly not enough water can get into it ----- so other media and methods of getting enough water into the vanilla orchid will be needed.