This is a regular discussion on the board.
Here is a link to the instructions.

Here is a link that might be useful: Moving a large fully leafed out hosta.

who is that guy who posted that.. pure genius.. lol

ken

you really are a smarty Ken!

So much a genius that he suggests growing hosta on a driveway!

I was planning on doing the moving in September. Would that be a good time to move them? I had once moved them in late winter when they were dormant and they also did very well then. It was just difficult to find where they were.

I think September in zone 7 is probably still too hot.
I'd wait till temps are down in the 70's or 60's.

The heat stress will really be tough on the plant. And it's very likely that in your zone, it could still be producing its later flush of growth. Either wait till late September or October.

And make sure you give her lots of water to go into the fall. She'll have had a lot of her roots cut and will need to take in lots of water.

the point of the link .. was that it can be done ANYTIME.. whenever.. when the muse strikes you .. when the shovel is in your hand.. etc ...

ken