Hi Ray,

Thanks for your reply. I checked the label, and it's actually a 0.4%
solution of IBA + fungicide. But it didn't say that it should be
diluted! In fact, it says dip the cutting and then just stick it in a
pot and wait. Are orchids more sensitive to these hormones than other
plants? Will the undiluted solution damage the plants, and how long
should one wait for results? TIA

Cheers,
Xi

Ray wrote:
This is an anecdotal response, but it's the best one you've gotten yet. Oh
yeah, and the "only" one, apparently.

First, you'll want to dilute that concentration significantly. For a 0.04%
starter, I'd recommend no more than about 0.5 ml/liter.

Yes, the hormone is absorbed primarily through roots, but it can also enter
the plant through other surfaces. I guess that's why it works when you soak
a rootless plant. If you subscribe to Alan Koch's (Gold Country Orchids)
thoughts, the underside of the leaves are the preferred surfaces.

I would guess that applying it to the base of a keiki would be OK, but you'd
probably want a formula that stays put like Keiki-Root from Plant Hormones
Canada. Apparently the application of such hormones spark root growth
systemically, not locally, or we'd see roots growing from many surfaces
after a soak.