The Riley article is fairly informative. Although I wonder whether growth
hormones used on edibles can get into one's system and would be reluctant to
apply it to fruits and vegetables, but orchids are a different matter since
one doesn't commonly eat them. But then again, I'm going to have to
check-out the ingredients of Blossom Set, which I use all the time but can't
recall reading the label for product contents -- perhaps it has growth
regulators.

.. . . Pam
Everything Orchid Management System http://www.pe.net/~profpam/page3.html

-----------------------------------------------------------------------------------------------------------

Rob Halgren wrote:

Larry Dighera wrote:

On Sat, 28 Feb 2004 13:33:05 -0800, profpam wrote in
Message-Id: :



The Press Enterprise article (2/28/04) -- Plant Food Makes Massive
Impression -- cites a new product --MegaGro, containing Gibberellic
acid.

Has anyone used this product on orchids?



I haven't tried it yet, but here's some information and an inexpensive
source for Gibberellic Acid-3:
http://www.crfg.org/tidbits/gibberellic.html

http://www.jlhudsonseeds.net/GibberellicAcid.htm



This comes up every so often, actually. However, being an 'old
fuddy-duddy' (technical term) myself, I'd probably avoid it. Jim Brasch
(http://www.orchidmall.com/hormones/) probably knows more than anybody I
know. He'd be my choice to answer a few questions.

Anyway, cytokines work differently in different tissues, and the
results can be different between genera, as well. So I wouldn't
generalize too much. Also, you may force flowering or growth, but is
that necessarily a good thing? If the plant isn't ready, you can bloom
it to death. That may work for the potted plant trade, but I'd wager
that you are more interested in keeping a specimen around for a while.
That isn't meant to discourage experimentation (go for it), but you
might want to experiment on some plants that you don't have a particular
attachment to. You may get excellent results, and if you do I'm sure a
lot of people would be interesting in hearing about it.

--
Rob's Rules: http://www.msu.edu/~halgren
1) There is always room for one more orchid
2) There is always room for two more orchids
2a. See rule 1
3) Sure beats working...

On Mon, 22 Mar 2004 16:11:17 -0500, Rob Halgren
wrote in Message-Id:
:

Larry Dighera wrote:

On Sat, 28 Feb 2004 13:33:05 -0800, profpam wrote in
Message-Id: :

The Press Enterprise article (2/28/04) -- Plant Food Makes Massive
Impression -- cites a new product --MegaGro, containing Gibberellic
acid.

Has anyone used this product on orchids?


I haven't tried it yet, but here's some information and an inexpensive
source for Gibberellic Acid-3:
http://www.crfg.org/tidbits/gibberellic.html

http://www.jlhudsonseeds.net/GibberellicAcid.htm


This comes up every so often, actually. However, being an 'old
fuddy-duddy' (technical term) myself, I'd probably avoid it.

You're not a fuddy-duddy; you're a realist. :-) You know there's no
free lunch.

Jim Brasch (http://www.orchidmall.com/hormones/) probably knows more
than anybody I know. He'd be my choice to answer a few questions.

From his web site, I'd expect he might know something about GA-3 and
orchids.

Anyway, cytokines work differently in different tissues,

That's an interesting bit of information. Are you able to describe
any of the differences?

Given that fact, I would expect different plant orgins/tissues might
be topically treated with GA-3 with different concentrations at
differing times in their growth, dormant, or differentiation phases to
provide results.

and the results can be different between genera, as well.

That fact almost demands empirical testing of GA-3, as I wouldn't
expect there to be articles available dealing with reed-stem
Epidendra.

So I wouldn't generalize too much. Also, you may force flowering or
growth, but is that necessarily a good thing? If the plant isn't ready,
you can bloom it to death.

When the chemical control system is wrenched from the hand of nature,
the new master must exert responsible adjustments that will not result
in too great a drain of plant resources. A slight increase in flower
size would be nice, but employing the GA-3 whip to exhaust all the
plant's resources would be abusive.

That may work for the potted plant trade,

How do they use it?

but I'd wager that you are more interested in keeping a specimen around
for a while.

Control of plant growth and enhancement of size could be useful tools,
but I suspect that "deficit spending" of plant resources may affect
future plant performance. However, if the GA-3 induced increase in
growth rate can be sustained with increased light, water, and
nutrients ...

That isn't meant to discourage experimentation (go for it), but you
might want to experiment on some plants that you don't have a particular
attachment to.

Thanks for the encouragement and warning.

You may get excellent results, and if you do I'm sure a
lot of people would be interesting in hearing about it.

I'll post what I learn.

On Mon, 22 Mar 2004 22:08:16 -0800, profpam wrote in
Message-Id: :

Although I wonder whether growth
hormones used on edibles can get into one's system and would be reluctant to
apply it to fruits and vegetables,

Here's some information about the safety issue with Gibberellic Acid:

http://www.jlhudsonseeds.net/GibberellicAcid.htm#SAFETY
SAFETY

GA-3 is a natural organic compound, and its use is approved by
most organic certification agencies.

GA-3 is considered 'relatively non-toxic'. According to the MSDS
(Material Safety Data Sheet), the LD50 (lethal dose 50) or the
dose which kills 50% of the test animals, is 1000 to 25,000
milligrams per kilogram of body weight in mice, dogs and rats.
Applied to humans, this would mean a 75 kilogram (165 pound)
person could be killed by consuming between 75 and 1875 grams (2.6
ounces to about 4 pounds) of the 90% GA-3 powder. "In reproductive
studies in rats, no maternal or fetal toxicity, or other adverse
effects to the fetus were noted following large doses
(1000mg/kg/day) of gibberellic acid." -MSDS. The powder may cause
eye irritation; in case of contact, flush with plenty of water.
Reporting this information does not imply our endorsement of
animal testing!

The relative non-toxicity of GA-3 and its use on food crops should
not encourage careless handling - always keep out of reach of
children, avoid contact with skin, eyes and clothing, wash hands
after using, or use rubber gloves. Do not use on food crops or for
any other purpose than seed germination research. Properly dispose
of toweling or filter papers after use, thoroughly wash
implements, then rinse with vinegar, then rinse again. Do not
contaminate soil - GA-3 is highly persistent and bioactive and may
remain in soil for some months and affect plant growth. A healthy
organic soil with strong microbial growth will probably break it
down fastest. Plants vary widely in their sensitivity to GA-3.
Remember that while GA-3 is sprayed on table grapes at a rate of 1
milligram per 1.7 square feet (26 grams per acre), that same
milligram could cause cone formation on 500,000 Cupressus shoots.
Remember that while GA-3 is naturally present in common foods like
corn, it is only in billionth of a gram quantities.

Obey all local, state and federal laws regarding use or disposal
of this product!

We accept no liability for use of this product or information!
Have a nice day!

Larry Dighera wrote:

Anyway, cytokines work differently in different tissues,



That's an interesting bit of information. Are you able to describe
any of the differences?



No, not formally. My last plant physiology class was 15 years
ago... My books are at least that old, and may be out of date.


That may work for the potted plant trade,



How do they use it?



Well, for example, if you want to sell mums or whatever in full
bloom, it wouldn't hurt to tinker with mother nature a bit to get more
blooms (or longer stems, see below). Here are a few concrete examples
(not all pot plants):

Gibberellic acid increases fruit set in blueberry
http://www.ipm.msu.edu/CAT01_fruit/F05-15-01.htm#6
Increasing stem length in pompom mums
http://www.actahort.org/books/167/167_11.htm
Gibberellins help prevent leaf yellowing in mums
http://www.endowment.org/projects/2002/reid02.htm
Improves germination of some seeds
http://www.actahort.org/books/73/73_18.htm

That will get you started... But obviously the effect on the seed
is different than the effect on the flower (blueberry), or stem (mum).


but I'd wager that you are more interested in keeping a specimen around
for a while.



Control of plant growth and enhancement of size could be useful tools,
but I suspect that "deficit spending" of plant resources may affect
future plant performance. However, if the GA-3 induced increase in
growth rate can be sustained with increased light, water, and
nutrients ...



Of course if you can keep a plant at optimum light, water, and
nutrient level, you are better than I... I suspect merely (_merely_!)
doing this would be a substantial improvement, regardless of GA
application. If you can get an improvement over this baseline, then it
is well worth it, however. It is a commercially viable process for a
number of crops, I can't imagine mum growers spending money to spray
with GA if it didn't improve their bottom line.


Rob

--
Rob's Rules: http://www.msu.edu/~halgren
1) There is always room for one more orchid
2) There is always room for two more orchids
2a. See rule 1
3) Always have at least three rules