Blue Hydrangea

I have had two blue Hydrangea plants in pots for Mothers day,how do I look after
them,and keep them blue,please

 

Hi Layla
I'm interested too. I have a couple that are pink and during the winter I mixed a handful of iron nails in their tubs to see if that would turn them blue. I also only use rain water.

 

I have been known to plant a coke can at the base of a hydrangea to keep it blue-the iron is to keep the foliage a vibrant green ( I think because that's what I use sequestrine for). I think aluminium keeps them blue.

 

I've had a browse and find both Ali & Iron methods are suggested. Obviously an Acid soil is required so I'll change the compost in the pots too just to be sure.

 

This is pasted from Heronswood Nursery, my favorite Hydrangea source. Recall reading this years ago--point is only certain species of Hydrangea are affected by soil pH.

No matter their nativity, Hydrangeas in general are woodland understory plants and thrive in moist but well-drained soils amended with organic matter (humus, leaf mold, compost).
Most species tolerate a range of pH conditions. However, the H. macrophylla and H. serrata cultivars are unique for their flower color being determined by the relative acidity of the soil: a pH below 6 (acidic) will usually produce flower color closer to true blue, whereas a pH above 6 (more alkaline) will produce flowers more pink. Add aluminum sulfate to soil to make flowers bluer or add lime to soil to make flowers pinker (apply to plant root zone in late autumn or early spring). If your soil is already extremely acidic (pH 5.5 or lower) or extremely alkaline (pH 7 or above), it might be very difficult or impossible to change pH sufficiently to change the flower color of your hydrangea.

 

will the white ones stay white, not sure if the plant i had was just a houseplant but it was white , i have put it in the garden last year ,and even though it did not die it did not flower last year, but this year it has grown bigger and has some good leaves coming on it already, so i will have to see if it will flower this year ,if not it will be 2 years on the trot that it has not produced any flowers.



when i had it as a house plant it had big white flowers

 

White flowering hydrangeas stay white. One reason for them not flowering in one year is probably that they had the last years growth pruned off, they flower on the previous years growth.

Is this a possiblilty May?

 

How effective if the stuff you can buy to make them stay blue? Never tried it. I had a hydrangea in a pot but it looked so unhappy I planted it out in moist shade and await the result of the colour of the flowers this year!

 

Never used it Aaron, but it is only temporary, you need to use it continuously or it will revert to the soil type already there. I have an Izu no Hana now kindly sent to me by Ivory which despite being badly damaged by frost is making good signs of recovery-I simply must keep it blue, so am reading the thread keenly.

 

I also have a Izu no Hana. Don't want to say color right now, too many out there, but do remember the name. I'll wait until it blooms.

 

when i put it in the garden i just took it out of the potplant
that it was in, and did not prune it , but since posting i notice that i can see some flowers maybe just starting to form, the greenleaves are getting really big now and i think i can see some flowers starting to form, and it seems to be further along than my other hydranga which is a pink one , which has been in the garden a few years now.

i wonder if the white ones are earlier than the coloured ones?

 

my white hydranga which was a house plant ,that i planted in the garden, has this year turned out a really nice sky blue in the garden this year .



the dog does his wee wee right by it , so maybe thats why.




And my other hydranga which started out pink, is the most deep purple i have ever seen in a hydranga. so if you want a really deep purple you will have to wee on it :lollol:

 

I'll re train my dogs to wee on the hydrenga rather than the box trees that they are doing a fine job of killing (or at least turning them very brown) lol

 

I've had some success planting in ericaceous compost and dosing with aluminium sulphate and ericaceous miracle grow. The aluminium makes it blue but it needs acidic conditions to absorb it.
You can also cut blue heads and lay them on the soil surface so they are reabsorbed to produce more blue next year.
It is a right faff though and so this year, I've just left it to its own devices and it's still lovely

 

I've been a bit baffled about this question of blue Hydrangeas ever since we moved into our present house nine years ago. Along the north facing wall we have a row of half a dozen - not sure of the exact number as they're so bushy and healthy - and the colours range from white, through pink to blue and mauve. Apart from dead-heading and occasional thinning we don't do anything to them and they always flower their heatrts out. Explain that!:hehe:
Chris