It's just a matter of how you choose to look at it.
When the new roots emerge they are all the same. Those that find
themselves in air adapt to that. Those that find themselves under a
layer of medium adapt to that.
Sometimes people talk about "air roots" as if they are a different
structure than the other roots. Perhaps some plants, maybe trees that
live in the tropics, have air roots that actually are a different
structure than the roots in the ground. I'm not sure.
With orchids, I still look at it as "roots is roots", and then they all
adapt to what they are growing in.

I was going to end right there but... the original poster was asking why
his plant was making so many air roots. I guess the answer to that would
be "because they are growing in the air". He also made a distinction
between air roots and "regular roots". I just wanted him to know that
those air roots WOULD have been regular roots if the plant sat lower in
the potting medium.

Steve


Ray B wrote:
I don't agree that "roots is roots", Steve. If that was the case, then
your comment that "the roots
that developed in the air will not be acclimated to live in the pot.
They don't die instantly, or anything but they do have a short life once
moved into the medium" wouldn't be correct, which it is, as root cells
"tailor" themselves to the environment into which they grow.

I tend to put phals into much larger pots than most - often with the pot
diameter equal to the leaf span. In those situations, I find that the
aerial roots redirect themselves down into the pot and grow just fine.
I like the aerial roots to "guy wires" on a tower. Phals are pretty
heavy and unstable on a relatively small base, so by grabbing hold
farther out from the base, the roots can stabilize the structure.

Ray Barkalow - First Rays LLC - www.firstrays.com
Orchid Plants, Supplies, Equipment, Books
Artwork, Free Services & Lots of Info!

-----Original Message-----
From: Steve ]
Posted At: Saturday, December 26, 2009 4:56 PM
Posted To: rec.gardens.orchids
Conversation: Phal Air Roots Question
Subject: Phal Air Roots Question
Vito,
First of all "roots is roots". Your air roots are just regular roots
that happen to be in the air.
Phalaenopsis just grow upward. New leaves form at the top, old leaves
die at the bottom and the new roots emerge just above or just below the
bottom leaves.
If you leave your plant in the same pot for years and you don't repot it

so that it is lower down into the pot, you would eventually have the
entire plant, including roots, hovering above the pot on an old trunk.
Sure, the old roots in the pot will sometimes start growing again and
they can branch, they eventually die off leaving the newer roots higher
up to carry on.
One more thing. When you repot your plant lower into the pot, the roots
that developed in the air will not be acclimated to live in the pot.
They don't die instantly, or anything but they do have a short life once

moved into the medium. Repot when there are new roots just starting to
grow.

Steve in the Adirondacks