Hydrangea feeding

Just new to this gardening. Garden I work in has hydrangeas - what is the best food/fertilizer to use on them. They are blue and the owner wishes them to remain blue. I am told that acidic soil makes them blue so what feed could I use.

islayhawk

 

I have this link saved in my favourites, but have never tried fertilizing them (I only have one client who has them and all I fertilize with, is a general fertilizer or a mulch of compost/manure)

Changing the Color of Hydrangeas

 

Hi islayhawk,
In addition to 'dim's helpful articles, ask your owner about the pH factor of the soil first, to be sure what you have to deal with.
I have a lot of h. macrophylla shrubs and they are mostly pink, although the soil on which they grow is mildly acidic (6.3 - 6.6).

However, reading your post, I remembered that in 2010, I tried to change the colour of one shrub. I squashed one or two lemons and soaked the peels in a jar of lukewarm water overnight. I added 1 litre of water to this solution and started watering one side of the shrub, while it was in bud (still green). I watered every day until it was in full bloom and this is what I got:


Sorry for the poor quality of the shots, my old camera was to blame.

Good luck and lots of nice blue flowering this season!