"Franz Heymann" wrote in message ...
"Mike Lyle" wrote in message
[...]
You may get
some failures with the usual compost-sand mixture, but at least the
successful ones are easy to plant on.

I assure you that it is easier to transplant the gel-grown cuttings safely
than it is to transplant compost-grown cuttings. I have elaborated on this
in another post to this thread.

I haven't seen the other post; I'll read it now.

I certainly wouldn't even
consider old-fashioned flour-and-water paste, as that would be covered
with moulds in no time. You could make an agar gel out of Irish
(Carragheen) moss, but I couldn't be bothered.

The agar would also be mould ridden if it did not contain a disinfecting (if
that is the word I want) agent.

You make it up by boiling the seaweed, so it would be sterile at least
to start with. Though the boiling would drive out dissolved oxygen,
which must be a bad thing.

The commercial gel and a commercial
wallpaper paste like polycel both contain an anti-mould agent

But we'd need to be sure the wallpaper paste one was as harmless as
the one intended specifically for plants, and that's what worried me.

I can't make up my mind about rooting hormones: there certainly are
some cuttings where they are said to do more harm than good, and with
others there doesn't seem to be much point. They do lose their
effectiveness in storage.

Thanks for that info. I have always wondered if I was squandering my
savings by religiously buying a new supply each season.

No, you've been doing the right thing.

The fear (unbacked by any evidence at all) of anti-fungal ingredients
is also what put me off using wallpaper paste as an experimental fluid
sowing medium. We don't really need these aids anyhow.

I don't agree with that last sentiment. I have not done it yet, but I would
be surprised if it did not turn out to be more convenient and safer to prick
out seedlings germinated in a gel than all that rough handling involved in
the use of a seed compost..

I certainly do damage a fair few seedings when pricking out, sometimes
by clumsiness, sometimes by having left them a bit too late (my
personal record is probably some cotoneasters which I somehow left in
the seed tray for five years!). I suspect the gel technique would be
to sow seeds individually as one would in something like a peat block,
rather than broadcast in a tray. I can see its potential value for
very scarce or expensive seeds; but I imagine one would need to learn
some new techniques.

It must also have enormous commercial value, as combined with fluid
sowing technique it would sharply reduce labour inputs.

Mike.