Moving a grape vine

Hi Heron, how old is the vine you want to move?

About four years MG It screens the South side of my GH, but (a) I have to keep it small and (b) I need more light as I've got another spanning the top of the GH. I want to cover a big arch with it.

Shouldn't be to difficult then, this is the info on moving a vine from UBC botanical gardens forum (which is the clearest I've read)

Moving a Grape vine that young should not be a problem.
Just start to dig in a circle about 2 feet from the base of
the vine. Dig straight down for the first foot or so and
then angle inwards toward the base. After you have the
circular cuts made and you have dug down a foot then
with the angular cuts the vine should be able to be popped
out with not a lot of trouble where you are. Here, it may
be a totally different story with our hard pan.

The area that I would have the most concern is whether
to lift the vine out when it is dormant or while it is still
green. Personally, I would rather dig it out right now
before it goes dormant. I like to give the Grape some
time to adapt to its new home before you get some
serious cold weather. The cane preparation is the next
major concern as I would leave about 4-5 scions on two
strong lateral (in opposite directions) canes. I would cut
the vegetative growth on the side nodes back to 2-3 nodes.
The reason for this is that we want to give the vine some
leaves not only to help the Grape but to let us know if the
Grape is not happy with us after our transplanting. Another
reason to cut the growth back just prior to moving the vine
is to allow the vine to produce root growth soon after it
gets over the shock of being moved. For a vine that size I
would give the vine 2-3 gallons of a liquid Vitamin B1
mixed with water at one fluid ounce per gallon of water a
few minutes after the vine has been transplanted to help
with the transplant shock.

Thanks for that Moon Grower, I agree that now would be the best time before it's dormant. I'll do it next week.

Good luck Heron!

Couldn't wait, moved it this afternoon as I want to re-plant the area. The roots were spreading shallowly and at a spades depth down the soil is very wet as there is a drain beneath it. This would not be ideal for a vine so it's as well I moved it.

Indeed it is Heron they grow best on dry, chalky soil. In the Mosel & Rhine they are basically growing through the rock. They actually have to use an auger to make a hole to plant a new vine.