Give it a good feed but I use the growmore type.

If you haven't moved it to a larger pot for the last couple of years, that could be the problem - its root bound. Turn it out of its pot and check the rootball, pot on if it is rootbound.

Hi, if it's been in the same pot for 4 years, it probably needs repotting, if you intend to keep it in a pot, I would pot it into j i no 3 loam based compost, Derek.

Hi Bamboo, sorry crossed again, Derek.

Snap, Derek... your answer wasn't there when I started typing, but it was there as soon as I'd posted!

Thanks everyone. I think it has made me decide to take out of pot which is probably too small now, and put in garden, as have not got room for larger pot, also quite expensive to buy. Now will have a pot to fill, any ideas for sunny spot on patio.

Is it likely to change colour in the garden depending on the soil?
just curious I haven't grown a white one......

Deutzia if you want white; Salvia 'cero posti' if you like deep pink; Lavender?

Hi Pam, no it should stay white, Derek.

Interesting.......

My hydrangea did start off as a white one, but yes it is a pale pink now, wonder if this always happens, do love white flowers.