This is a public-interest archive. Personal data is pseudonymized and retained under GDPR Article 89.

Re: European Geraniums

Duncan, 
Yes, I know that I am a sucker for a good question.  
Rick

> On 26/04/97 00:49, in message <3361B382.57EF@eskimo.com>, Duncan 
> McAlpine <mcalpin@eskimo.com> wrote:
> 
> I purchased a plant last year. To get free cuttings for next year....cut
> a portion off of each trailing vine with a node. When you have the node,
> cut the node in half with a razor blade down the length of the stem.
> Place the stem in media.

> Michael Open responded:
> .... Don't know if this is an improvement on something that works, but
there was 
> an article in a British gardening magazine a few years ago on Pelargonium
cuttings. 
> The gist was:
> a) leave cuttings for twentyfour hours to dry off after trimming and
before planting.
> b) Don't use rooting hormone.
> c) The best time for taking cuttings is the end of the growing season,
but not after 
> growth has stopped. In our part of the world that means Aug-Sept but not
Oct.

My typical technique is to callus the cuttings (Michael's leaving the
cutting out to dry for a day or so); 
dust the cuttings in a fungicide and a gentle softwood rooting hormone
(Hormodin #1); take green or semi-hard cuttings (this season's growth). 
This works for xhortorum and peltatum types, including the Balcon types. 
Also works for most of the species in section Ciconium.  In this section, I
will successfully take and root cuttings year-round, but the plants need to
be actively growing.  

I would not cut into the nodes, though.  The disease risk is too high, at
least in my hands (see below).  I just cut, callus for 24 to 48 hrs, and
stick.  

Too much hormone (too high a concentration) will reduce the take.  It's
like too much of any good thing ...

Media moisture is critical.  Enough, but not ever too much.  The media
should drain quickly and thoroughly. 

Cleanliness is also critical.  Clean pots / trays, clean (sterile) knife /
razor.  Follow-up fungicide drench.  

Are the chemicals necessary?  No.  You'll only lose about 20% of your
cuttings if everything is clean AND you neither dust the cuttings nor
drench the flats with a fungicide.  That's my actual success rate by the
way, when I choose not to use a fungicide in my own house.  

I have geranium friends who NEVER use a knife to take cuttings, because it
spreads disease.  They break them off by hand.  I use a knife and rinse it
in 70% ethanol between plants (although not between cuttings).  And yes,
this could also account for some of my 20% losses.  

Is a 20% loss critical?  To me, in a hobby greenhouse, I think not.  If I
were running a commercial greenhouse, that would my profit.  

A strict commercial operator would buy in tested disease-free cuttings
every year, and use those to start stock plants, from which production
cuttings would be taken.  There are many many diseases that carry over in
wintered-over stock plants.  These geranium diseases may not kill the plant
(or cuttings taken therefrom), but they will have a clear impact on the
health of those cuttings.  Again, to a hobbyist, this may not be a big
deal.  To a commercial grower, however, it is.  

My 20% losses are almost all due to Botrytis.  The cut end of the cutting
turns black and doesn't root.  A fungicide dusting and follow-up drench
would eliminate this.  It's just that I don't propagate a lot at one time,
and it's not always worth the time to me to mix up the drench, or to get
out the dust.  

A squeaky clean greenhouse would also reduce the loss.  Botrytis is
airborne, with the spores forming on dead leaves or plant material.  Think
about the grey "dust" that you see on grapes in the vineyard when they rot.
 That's Botrytis, and the same fungus can infect your geranium cuttings.  I
have to admit that vacuuming and sanitizing the gravel-covered greenhouse
floor is not a very high priority for me.  I feel good when I am lucky
enough to keep things dead-headed (and dead flowers are a good source of
Botrytis spores).  Therefore, there is a pretty high population of Botrytis
spores floating around my greenhouse.  Is this a problem?  Probably not. 
But it does contribute to my cutting losses.  

---------------------------------------------------------------------
To sign-off this list, send email to majordomo@mallorn.com with the
message text UNSUBSCRIBE PERENNIALS.
Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index