Thanks Julia, I had a feeling that might be the case. I was wishing that they could be high up somewhere so that we could see their faces, but that can’t be done.

The time to move them is late summer/early autumn. They will happily make new roots then. So if you can wait then that would be the best.

Its when I've moved mine.

If you have to move them sooner, lift with as much soil around them as you can. But be careful as that can be a very heavy root ball. [I know I had to do it 5 years ago, and it sulked the following season, flowers ok now though]

Well ...I had a lovely little double white one that had got overgrown by a now large shrub so last year I moved it a yard or two away into the light. This year there was no sign of it, but where I planted the white double there is a single pink!

They also hate having their roots dry out. When I have had to move them in our previous garden where they grew like weeds, I used to take a bucket of water and put the plant in it while I moved it to a new spot.

I put 2 of ours in pots last year from the borders. I think it was after flowering but can't be sure. They've both flowered profusely, despite summer neglect.

Thank you everyone for very helpful comments.