I know it does depend on the soil - I am looking for a really deep blue hydrangea.
Can anyone recomend a variety and where I can purchase one.
We were told to bury a horseshoe with the plant to turn it blue. I do not think they are naturally blue.
Colour depends upon whether the plant can get aluminium or not; if it can, the flower will be blue, otherwise it will be pink. If you have acid soil, aluminium probably is available to the roots (so you get blue flowers), in alkaline soil, the aluminium is locked up so pink flowers.
Haven't heard the horseshoe thing before, but maybe a bit of rusty iron provides the appropriate chemistry to free up some aluminium ions in the soil? Frequent dosing with aluminium sulphate fertiliser will let you grow blue flowers on a chalky soil, if that's what takes your fancy!
I'm confused ???
In the plant catalogues you get a choice of blue or pink. I do have a blue hydrangea, but it has a white centre and can look a bit insipid. What I was looking for was an deep intense blue.
It look as if I shall have to buy one marked "blue" and pour lots of aluminium sulphate fertiliser.
Thanks
Quote from: Shirley on February 12, 2007, 18:38:00
I'm confused ???
In the plant catalogues you get a choice of blue or pink.
Probably the same catalogues that you can get black fuchsias from.
I have googled blue hydrangeas and they even have blue names, I expect they are treated with a blueing agent and you have to keep up the treatment if you do not have an acid soil.
I bought some beautiful blue hydrangeas from B&Q. However during their second season they reverted to pink! Seems I should have tried aluminium sulphate.
Anyone living somewhere with acid soil and a garden full of camellias and heathers and azaleas is probably wondering what all the fuss is about :)
As Shirley says she already has a blue one growing OK and it hasn't turned pink, she is probably fine to buy one that looks good in the catalogue and expect it to turn out right!
The growers that produce blue/Pink varieties have facilities to keep them this way.
Later after planting out the chemical/s they have been treated with leeches out resulting in plants looking a bit insipid i.e. they have lost the intense colour they were when bought.
The only way back to this intensity is to treat them again.
There is a bit about how to do it here; http://tinyurl.com/yb4g8c
Thanks for all the information and that page to which you referred is very good. Will buy a "Blue" shrub and feed it constantly
Mum use to keep her brilo pads for them one year she bought the powder and mixed it in a watering can. Dad saw it and used the water to water his beetroot. Mum was not happy ha ha.
But treatment yes.