Hi, the best time to move, or divide Agapanthus, is in spring, they have fairly thick, fleshy roots, so you may have a problem disentangling them from the roots of the Hydrangea, good luck, Derek.

I too would wait until spring.

Thank you both I'll leave it so until Spring. It's a pity I have to move it at all but it's the same colour as the Hydrangea white and the beauty of the Agapanthas is being lost.