Hydrangeas

[Steve Newport]

Think thats how you spell it.

Should I cut these down at this time of year? (New to this gardening
thing)

Also, years ago my grandfather told me that to help get blue flowers
you could sprinkle potassium permanganate around the roots. Is there
any truth in this or was he having me on?

[Stewart Robert Hinsley]

Post by Steve Newport
Think thats how you spell it.
Should I cut these down at this time of year? (New to this gardening
thing)

What I've read is that in the case of Hydrangea macrophylla (i.e. not
the aspera group, not petiolaris, not quercifolia, etc) you should dealy
pruning until the spring, so that the old growth protects the new ground
level shoots from frost. Also that you should only cut out one third
(the oldest third) of the stems each year, as otherwise you end up with
a lot of frost-tender wood, and a less vigorous plant.

Post by Steve Newport
Also, years ago my grandfather told me that to help get blue flowers
you could sprinkle potassium permanganate around the roots. Is there
any truth in this or was he having me on?

Soil chemistry does effect Hydrangea flower colour, but Potassium
Permanganate doesn't run any bells. Moreover I recall that it's rather
aggressive chemically.

Aluminium Sulphate or Potassium Aluminium Sulphate are compounds
mentioned on the web as bluing agents. An alternative is to acidify the
soil to make aluminium more available.

I've also seen mention of adding iron (in the form of nails) to the
planting hole to obtain the blue effect.

[Brian]

Post by Steve Newport
Think thats how you spell it.
Should I cut these down at this time of year? (New to this gardening
thing)
Also, years ago my grandfather told me that to help get blue flowers
you could sprinkle potassium permanganate around the roots. Is there
any truth in this or was he having me on?

~~~~~~~~~~~~~~~
Leave the present blooms throughout the winter. They protect the next
year's flower buds from frost. After a bad winter there used to be no
flowers! Just break off[easily] the dead flowers in the spring and only
prune out any branches that need to be removed.
Nothing seems to work, in the long-run, that will change the reds to
blue.
I sometimes wonder if those who can only grow blue wish for reds?
Best Wishes Brian.

[Tumbleweed]

Post by Steve Newport
Think thats how you spell it.
Should I cut these down at this time of year? (New to this gardening
thing)
Also, years ago my grandfather told me that to help get blue flowers
you could sprinkle potassium permanganate around the roots. Is there
any truth in this or was he having me on?

a few iron nails (ones that will rust) in the soil, IIRC. Or ferrous
sulphate to be quicker, again IIRC but I would think a quick google would
confirm it.

[sam]

Post by Steve Newport
Think thats how you spell it.
Should I cut these down at this time of year? (New to this gardening
thing)
Also, years ago my grandfather told me that to help get blue flowers
you could sprinkle potassium permanganate around the roots. Is there
any truth in this or was he having me on?

Hydrangeas are calcifuge i.e. lime haters, and need an ericaceous
compost to show true-blue colours. Some are naturally not blue but
adding blue dye to the soil makes them look a bit unnatural.If yours are
in containers now would be a good time to change the compost. If they
are in the soil you cannot change that so give it a good dose of
chelated iron instead.
Sequestrene is a good propriety brand.Use according the instructions.
There are also several ericaceous fertilisers both liquid and granular
which can be added during the early growing season.The transformation
is sheer delight.(Camelias,Rhodendrons, and Azaleas are three more
popular plants which fall into this category).
Good gardening - Sam.