IIRC Superthrive is vitamin B-1 with some other plant hormone, but the real
ingredient is the B-1. So, just as B-1 softens transplanting shock so
Superthrive will help wiht repotting shock.

IIRC humic acid is the acid that makes tropical river water dark, its from
broken down plant material. Sure there's some plant hormones in there too,
but in general its acidity is what hold back or causes decline in potted
plants, the salts and acids build up in old potting soil - soil I hastens to
add!! I'm talking about house plants here, not orchids - and the plant fails
to thrive. You repot and voila, better blooms growths etc. Less burning
of those delicate root hairs.

Now what humic acid may or maynot provide to *orchids* is another horse
entirely, IMHO. There have been any number of peopel who like use of a
variety of natural fertilizers. Alan Koch liked using the algae additive
(of course I'm blanking on its name.... some sort of Icelandic algae, has a
variety of plant hormones which increases rooting, growth, etc.) I used to
use it and did see improvement. Of course, as Wellenstein says, you never
know whether the plants are responding to 1) repotting 2) better watering
because you are paying better attention 3) or the stuff you are using.

So its a double edged sword. Ray, I think what you are seeing is just the
usual increased solubility of inorganic micronutrients that any
acidification/fertilizer would bring to solution. Marschner ( "Mineral
Nutrition of Higher Plants") doesn't have an index listing for Humic acid,
or even humus. There's nothing in the old AOS Bulletin under Humic Acid and
the only 2 possible articles are in regard to CAM.

Here's a link to humic acid and follow the link to Leibig:
http://en.wikipedia.org/wiki/Humic_acid

K Barrett.


"Diana Kulaga" wrote in message
. ..
Without going out to look at the SuperThrive bottle (lazy girl!), is humic
acid one of the ingredients in that product? I began using ST this year,
and I can't believe the results. They should hire me as a spokesperson for
the stuff. The pbulbs are far stronger and bigger, and the flowers are
more numerous and also larger.

Diana

"Ray B" wrote in message
...
Many moons ago, when I was experimenting with developing my own,
better-but-much-cheaper SuperThrive (abandoned, due to EPA regs), I began
using humic acid as an additive to the formulation.

I am quite certain of its benefit in soils, as it helps release
otherwise-sequestered nutrients, but I questioned its applicability to
orchid-growing.

I know this is quite unscientific, but about 4 months ago - just before
the time I had to start mostly "ignoring" my collection due to the
various surgeries I endured - I added a liquid humic acid concentrate to
my fertilizer feed tank, so have been feeding with it (it ends up being
about a teaspoon per gallon), and it "looks" like it may be a "plus"
after all, as I am seeing more growth and blooms than I had been (again
I'll state - it's quite an unscientific assessment).

Anyone else have any thoughts or experience?

--

Ray Barkalow - First Rays Orchids - www.firstrays.com
Plants, Supplies. Books, Artwork, and lots of Free Info!