Article 10669 (111 more) in rec.gardens:
From: klier@iscsvax.uni.edu
Subject: Re: plant root hormones?
Date: 10 Sep 92 22:28:49 GMT
Organization: University of Northern Iowa

> ROOTONE is advertised as a plant root hormone that encourages cuttings 
> to grow roots and become real plants.  Has anybody out there ever used 
> ROOTONE or similar substances?  Can someone send my a list of plants 
> that will respond to this stuff, or point me to a FAQ list?

Rootone and Hormonex are a couple of brands of synthetic rooting hormones--
and I use them all the time in the greenhouse when I'm striking cuttings.
These come in a variety of strengths (they are auxin analogs), and you
just dip the last few nodes into the powder, tap the excess off, and stick
the cutting into the rooting media.

Here's where the fun starts: IAA and its analogs _inhibit_ root growth 
at high concentrations, and the listings on the sides of the cans or
packets generally talk about only a few common species.  Some species
will root in single-strength Hormonex, but won't root in higher 
concentrations.  Another species wouldn't root at lower concentrations,
will root at double strength, and won't root at highest strength....

My seat-of-the-pants guide for which strength to choose is lowest
strength for herbaceous plants, middle strength for most vines/trees/shrubs,
and highest strength for hard-to-root plants like conifers. 

If I've got plenty of plant material to play with, and I really don't
know how this species will respond, I put some untreated cuttings in 
the mist bed, and some treated with each of the concentrations on hand.
Then I get out that underutilized best tool, the notebook, and start 
taking notes.

If I don't have much, I try untreated and treated with lowest concentration.
Then if I see no roots in 6 weeks, I'll bump it up to medium conc...
For the absolutely most stubborn, hard to root plants, I use very dilute
2,4-D, which is also an auxin analog (it essentially kills at
herbicidal concentrations by "growing the plant to death").

Why do I use Rootone, etc.?  Well, if you get the right concentration,
the cuttings _do_ root much faster and come out of the mist bed much 
sooner than if I had untreated cuttings.  Our mist bed isn't very big,
and we all have to share the space, so "KLIER, GET YOUR D**N CUTTINGS 
OUT OF HERE!!!!"  There is also a little fungicide in most preparations
and that seems to help improve the survival.

I don't have a list of what plants need what strength.  The commonly
available Rootone is the lowest of the 3 concentrations available--
it's an OK choice for most things.  I suspect that a professional plant
propagation manuals have tables of all this, but I don't own one. 
Just need to hit a few more booksales and used book stores!  ;-)

Kay Klier  Biology Dept  UNI

----*----

Article 10771 (106 more) in rec.gardens:
From: drewsxpa@salem.intel.com (Paul Drews)
Subject: Re: plant root hormones?
Date: 15 Sep 92 18:37:40 GMT

>ROOTONE is advertised as a plant root hormone that encourages cuttings 
>to grow roots and become real plants.  Has anybody out there ever used 
>ROOTONE or similar substances?  Can someone send my a list of plants 
>that will respond to this stuff, or point me to a FAQ list?

Just a few things to add to Kay's excellent reply:

A  good  reference  book I use is "The reference manual of woody plant
propagation".    It   has   an   excellent  discussion  of  chemicals,
techniques,  etc.   along with specific information for a wide variety
of  woody  plant species.  No info on rooting techniques for non-woody
plants, although my sense is that you use lower concentrations and get
quicker  results.   I  can  get an ISBN and so forth for the book from
home if you can't find it in a well-stocked gardening bookstore.

This  book  mentions  three hormones:  IAA (I can't remember what this
stands  for.   It  was  had no effect or an inhibiting effect for most
things).   NAA,  which  stands  for "Naphthaleneacetic acid".  This is
used  for some woody plant propagation, but isn't too effective.  IBA,
which  stands  for "Indole-3 Butyric Acid" is the most popular rooting
hormone for woody plants.  I have the vague impression that NAA may be
more widely used for the non-woody plants.

NAA and IBA are solids at room temperature.  They are either dissolved
in  an  alcohol-water solution or mixed with talc powder for use.  You
typically  buy them this way, since only tiny amounts are required and
the  chemicals  are  very expensive and poisonous.  Here's a couple of
products:

Rootone:
NAA  with talc, although I once found a packet of this way in the back
of  the pile at some store that claimed to have IBA.  I vaguely recall
that  the  concentration  was  0.01%  which  is  way  too low for most
woody-plant  use.   I  have used it successfully for non-woody plants,
though.   This  is  usually  the  only  one you can find in your local
gardening store.

Hormex:
IBA  with  talc.   Comes  in "number 1, number 5, number 8, and number
16",  with  the  number indicating the concentration (number 8 is 8000
PPM,  etc.).   As  Kay  points  out,  too  low  a concentration is not
effective,  too  high  "burns"  the  plant.  Hormex number 8 is a good
mid-range for the woody plants.

Hormodin:
IBA  with  talc.   Comes  in  1,  2,  or  3,  at  1000, 5000, 8000 PPM
respecitvely.   Check  the  bottle  label  for  exact numbers.  When I
bought some of this stuff, it came with a table of a couple of hundred
woody  plant  species  together  with the proper hormodin number to go
with them.

Dip-N-Grow:
IBA  in  alcohol-water  solution.   I  think  I  got it in a 10000 PPM
solution intended to be diluted with water.

There  are  more,  but these are the ones I have experience with.  You
can  find  Rootone at most gardening stores.  I had to go to a nursery
supply  place to find the others (Teufel nurseries in Portland, Oregon
in  my case).  The talc formulations are the easiest to handle and use
in my opinion, although the solutions may have slightly higher success
ratios.

The  most  common recipe for use (for deciduous hardwoods) seems to be
to  take cuttings in june-july, dip the ends of the cuttings and knock
off  the  excess.  Stick them in moist a perlite-peat mixture and keep
them from drying out.  They will dry out very easily, since they don't
have  any  decent root systems to suck up water yet.  You have to keep
them  moist  and  shady.  I have used a mist bottle twice a day with a
saran  wrap  cover,  but  still dried out quite a few.  I envy Kay her
greenhouse  and  automated misting system.  Start with some easy stuff
like  willow,  wisteria,  poplar, and dogwood first to get the hang of
it.

For  the  few conifers that will root (the redwoods, yews, some cedars
and  junipers (I can see the botanists shuddering at my classification
system))  the  magic  formula  seems  to  be to take fall to midwinder
cuttings.   These  do  best  with cold tops and warm bottoms.  I don't
have  the  equipment  for this, so I will be experimenting this winter
with cold-all-over techniques.

By  the  way, the rooting hormones are dreadfully poisonous.  Read the
caution  labels on the containers.  Don't even store them near food or
fertilizer and don't use them on stuff you're going to eat.

                                - PauL Drews
                                drewsxpa@ashland.intel.com
