Ooh that's a difficult one! I agree with Giraffe that if the bride is in a meringue it would be fine but if she is in something less weddingy such as a white fitted dress in a similar length then it may be too white.
You would need coloured accessories not metallics & maybe a coloured cardi/jacket/shrug just to emphasise the non whiteness of it.
It s a lovely dress but on reflection I would probably choose another one. Plus it may just be me but I find the placement of the blue flowers a little odd/mingey...?