Posted: 31/07/2016 at 09:33
In theory, you'd wait till it's dormant for the best chance of success, but that's not always possible.
The advice is still the same - give it a thorough soaking, prepare the new hole where you're moving it to, and then dig it out with as big a rootball as possible. Once it's in the ground, water it thoroughly and then keep an eye on it to make sure it doesn't dry out. For a big shrub like that, I'd take the flowers off and prune it back a bit. I know that seems a shame, but transplanting can shock mature shrubs, and removing some of the top growth helps to relieve the stress on it and gives it a better chance of recovery.
The heucheras will be easy to move - they're very forgiving anyway, but keep them well enough watered till established. The rhodie/azalea next to the hydrangea will also be fine - again, water well before moving and make sure it doesn't dry out till established. It looks a little chlorotic so it may need a feed to green it up a bit. You can attend to that later though