On Tue, 2 Jun 2009, Chris Hogg wrote
On Tue, 02 Jun 2009 13:33:15 +0200, bob wrote:

On Mon, 01 Jun 2009 20:56:26 +0200, bob wrote:

I'm in France at the moment and couldn't find Sequestrine (or sulphate
of ammonia, come to that), nor could I spot an equivalent product in
the garden centre here so I'll go with the vinegar for now until I get
back to the UK to pick up supplies.

After a new search in my garden center I'm hoping what I've found
today is the approximately matching stuff in France - 'KB-anti
chlorose'. It's a powder, the bluish colour of a corroded copper
roof, and seems to have the principle ingredients soluble iron - 3%,
magnesium oxide - 16%.

It recommends a 10 grm dose in 2 litres of water for a single plant
and then a watering in to take the solution down to root level.
Subsequently monthly if necessary - but I don't know how one would
gauge the neccesity. It's not cheap so I don't want to splash it
around unnecessarily.

Do you think a repeated use is a sensible insurance policy or likely
overkill?

Never heard of the stuff, and the analysis makes me suspicious that
it's not the same as Sequestrine, especially the colour and the
presence of magnesium sulphate (it wasn't manganese by any chance, was
it? I suspect not, at that concentration). It could simply be a
mixture of iron and magnesium sulphates, both of which are important
in making leaves green (magnesium is a key component of chlorophyll).
It would probably be OK in the short term, but I doubt if it would be
of long term benefit if you were actually on alkaline soil. But as
it's only to offset the effect of hard water applied occasionally, I
guess it will probably be OK. When dissolved in water, it will be
slightly acidic itself, which will help. I wouldn't use it any more
frequently that it says on the packet, or if no instructions, then no
more than once per month.


I had a google on www.google.fr and the Jardiland advice pages for June
also said to use an 'anti-chlorose' product on Rhododendrons and azaleas
now - actually, they say it should be a 'complement soufré
antichlorose', which I presume means 'sulphated'. They also suggest
pruning now:
http://www.jardiland.com/nos_conseil...ison/469/index.
html?id=79&saison=3


Does Sequestrene have sulphur in it? Sequestrene itself can apparently
be bought in France and is called an 'anti-chlorose', so I suppose that
is the term for what they use on acid-loving plants. We've got a French
garden of a few inches of topsoil on solid limestone, so I have azaleas
in pots - we filled the pots with 'terre de bruyere' and every so often
give them a sprinkle of a bog-standard Intermarché product labelled for
azaleas and hortensias (hydrangeas), but more extensive planting would
be doomed on our soil, I think. How nice to have an entire acid patch!

--
Kate B

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