My lovely blue hydrangea has gradually over 5 years changed its colour to a mauvy dirty pink with purple tinge.

I understand i can bring the blue colour back by using acidic fertilizers..... What best choice products do you recommend from a uk garden centre or maybe from B&Q Also what product would give the quickest result.

I know pure peat is acidic but i dont wish to use peat even if it was available in the stores.

Your help would be appreciated.
Regards
Ken

"KEPPY" wrote
My lovely blue hydrangea has gradually over 5 years changed its colour
to a mauvy dirty pink with purple tinge.

I understand i can bring the blue colour back by using acidic
fertilizers..... What best choice products do you recommend from a uk
garden centre or maybe from B&Q Also what product would give the
quickest result.

I know pure peat is acidic but i dont wish to use peat even if it was
available in the stores.

The problem is that in alkaline soil they cannot take up the aluminium salts
they need to remain blue as they are locked up with other salts. Try
watering with Sequestered Iron and/or spreading coffee grounds around the
plant, these should help to acidify the soil.
Think I've seen an article on such in The Garden magazine recently.
--
Regards Bob Hobden
Posting to this Newsgroup from the W. of London UK

On 10/9/2011 5:29 PM, Bob Hobden wrote:
"KEPPY" wrote
My lovely blue hydrangea has gradually over 5 years changed its colour
to a mauvy dirty pink with purple tinge.

I understand i can bring the blue colour back by using acidic
fertilizers..... What best choice products do you recommend from a uk
garden centre or maybe from B&Q Also what product would give the
quickest result.

I know pure peat is acidic but i dont wish to use peat even if it was
available in the stores.

The problem is that in alkaline soil they cannot take up the aluminium
salts they need to remain blue as they are locked up with other salts.
Try watering with Sequestered Iron and/or spreading coffee grounds
around the plant, these should help to acidify the soil.
Think I've seen an article on such in The Garden magazine recently.

Aluminium sulfate works well.

On 10/10/2011 08:28, Jake wrote:
On Mon, 10 Oct 2011 07:30:04 +0100, Chris wrote:

I'm never clear on whether it's iron or aluminium that makes
hydrangeas blue. I know that an acid soil is necessary, and in such
soils both aluminium and iron are available. Adding either iron
sulphate or aluminium sulphate to the soil will acidify it, releasing
both aluminium and iron, so it's not clear which actually does the
biz.

AIUI, sequestrine doesn't actually acidify the soil, but provides iron
(and manganese) in a form that's soluble at high pH and that the plant
can absorb. But sequestrine doesn't provide soluble aluminium. If
sequestrine is sufficient to turn hydrangeas blue, then it suggests
the key requirement is iron. But does anyone know for certain that
sequestrine works? Alternatively, does anyone know the definitive
answer as to whether it's iron or aluminium that's necessary for blue
hydrangeas?

Everything I've ever read says that hydrangeas need both an acid soil
(pH 5.2-5.5 is ideal) and aluminium to be blue. Aluminium sulphate
will provide both but it has its drawbacks - use too much and it'll
damage the roots and it can be very damaging to young plants (under
2-3 years old).The recommended approach seems to be to use aluminium
sulphate in one year and sequestered iron in the next.

Cheers, Jake
================================================== ==========
URGling from the less wet end of Swansea Bay where it's ....
wet!

www.rivendell.org.uk

I think ammonium sulphate is more widely available and, according to
some, also works on hydrangeas. Judging by the smell, the ammonium part
seems to be released when mixed with water.

KEPPY wrote:


My lovely blue hydrangea has gradually over 5 years changed its colour
to a mauvy dirty pink with purple tinge.

I understand i can bring the blue colour back by using acidic
fertilizers..... What best choice products do you recommend from a
uk garden centre or maybe from B&Q Also what product would give the
quickest result.

I know pure peat is acidic but i dont wish to use peat even if it was
available in the stores.

Having recently bought a blue hydrangea that is yet to be planted out I
was looking into this very subject at the weekend.

According to the tag on my specimen (Hydrangea Macrophylla 'Zorro
Blue') the pH shound around 4.7 and althought the flowers are now
starting to die the vibrant blue is lovely. The Hydrangea at the front
of the house is pink and although this will planted in the back garden
I am assuming we have alkaline soil in general.

I will probably try
http://www.vitax.co.uk/index.php/are...st-products/vi
tax-hydrangea-colourant/ but only because another Vitax product had
been recommended to us by staff at RHS Wisley (for another issue) so
I'm hoping that their stuff does a good job in general.

--
Chris

On Mon, 10 Oct 2011 09:41:07 +0100, stuart noble
wrote:

I think ammonium sulphate is more widely available and, according to
some, also works on hydrangeas. Judging by the smell, the ammonium part
seems to be released when mixed with water.

Aluminium sulphate is available on eBay and Amazon if that helps. If
nothing else, it will help to keep slugs at bay! IIRC the hydrangea
colourants need to be applied very frequently.

Cheers, Jake
================================================== ==========
URGling from the less wet end of Swansea Bay where it's ....
wet!

www.rivendell.org.uk

In article , KEPPY
writes
My lovely blue hydrangea has gradually over 5 years changed its colour
to a mauvy dirty pink with purple tinge.

I understand i can bring the blue colour back by using acidic
fertilizers..... What best choice products do you recommend from a uk
garden centre or maybe from B&Q Also what product would give the
quickest result.

I know pure peat is acidic but i dont wish to use peat even if it was
available in the stores.


When I was a small boy (oh, so long ago!) we had a hydrangea growing in
a large wooden tub. My father's was of keeping it blue was to drive a
very large iron nail into the side of the tub.

At this distance in time I can't remember if it worked.

Roy.
--
Roy Bailey
West Berkshire.