Steven:

You can bury one of the vines to form roots. Then move it or leave it in place. Since you like the current fruit why not stick with that. A Concord from elsewhere should be alright. But any one you buy may not be the same as what you are working with now. You won't get much fruit for 2-3 yrs on a new vine.

As for the vines 20 ft up a tree, they are not helpful but don't really hurt anything as long they don't hurt the tree. If it were mine I'd cut them out. But you could also pull them out of the tree and train them along your fence. They will produce fruit until you can root one of them to produce your own vine.

If you haven't figured it out already, grapes produce fruit only on last yrs wood. So fruit next yr will be on this yrs growth but not on anything older. So you need to figure that into anything you do and as you learn how to prune your own vine someday. Grapes are a lot of fun to work with!!

The Fruitnut

Consider air-layering to propagate if the vines cannot easily reach ground on your property. A porous breadbag or even hacked-up soda bottle packed with moist potting media around the stem could be used to root the vine in mid-air. After roots develop just cut the stem on the parent plant side and plant you new seedling.

Proper variety selection is key for success in growing grapes, so don't just buy what home depot or anybody else just happens to have in stock. Not knowing your climate zone, I would suggest Jupiter or Glenora grapes available from Starkbros.com, among others.

An advantage to having the vines rooted in your yard is that you could train and prune them for larger grape size. My neighbors generously let their Concord vine sprawl over the back fence, knowing the Concord is one of my favorite grapes, but the grapes are only half the size of what a trained and pruned grape vine would produce.
Grape vines are easy to root from cuttings, so you could try rooting several one gallon pots of four cuttings each after next winterÂs pruning. They may produce in their second year, or really start going in their third. If you really like that variety, itÂs worth the wait. Much better than getting some unknown cultivar, and discovering after a few years that itÂs tasteless, doesnÂt ripen there for you at all.

Fruitnut (& Snorky),

I hope this doesn't come across too nitpicky, but I thought your statement "grapes produce fruit only on last yrs wood" could be clarified/expanded to help with pruning. My experience is mostly with muscadines, but the process is the same. Fruiting occurs on current growth that emerged from last year's growth. So that means when I prune in late February, if I prune off all last year's canes I'll get nothing in the current year. I do prune each cane back severely, but leave one or two buds of that cane at its base. From these remaining buds, new growth emerges and produces the new crop. Then the process repeats itself and those canes are cut back to one or two buds for the following year. This way a vigorous vine like Concord or a muscadine doesn't swallow your backyard. In your case Snorky, the first step would be to establish the roots on your side of the fence, then the permanent framework, i.e. trunk and arms, then in subsequent years do the regular pruning.