I have a 4 foot tall fence, and the concord grapes do great. Zero maintenance, I don't prune them, too many grapes to eat. I just chop back any that grow too long, and mow over the vines that extend out into the lawn.
Only drawback is the neighbors who love their lawn chemicals. Grape are very sensitive to weedkillers. One vine produces grapes only occasionally, and gets nipped back most years. Thinking of digging up the
root and planting elsewhere.
I had a
volunteer grape plant that did resist the chems very well. Sadly, the grape quality was poor, a cross between Concord and wild grapes, I suspect, and bit too bitter for eating, so I cut it back. I am watching the other volunteers to see how they do as regards to chems and flavor. So far it seems I either get great flavor and poor chem resistance, or, the opposite.