Concord Grape Vine Transplant & Pruning
I was hired to fix and replace a deck railing system and remove a grapevine a new homeowner did not want. I'm guessing the vine is at least 10-15 years old.
This vine had grown upward about 12 feet from its main trunk and at the time of cutting, the topmost vines were interwoven into the deck lattice, and producing a lot of fruit.
Upon removal in fall, the main trunk was cut about 4 feet from the ground, which removed all the new, fruiting growth. It was cut with no intention of anyone transplanting it at that time.
Fast forward to this spring, and the 4 foot stump started producing buds and growing, but still needed to be removed at the owners request. I decided I'd like to try to transplant it at my house.
I dug it out saving as much of the root system as possible, stuck the root base in a kiddie pool of water for 2 days, and surprisingly to me, growth continued, so I dug a hole and planted it. It has been in the ground 2 weeks, watered daily, and is continuing to grow and climb up a trellis I made for it. My goal is to have it climb the trellis upward to an arbor roof, and spread out across the canopy, with the main trunk/trellis located in the center of the arbor, and hopefully be able to harvest grapes from it when it is ready.
My questions surrounding this goal are:
1) when and how (if at all) should I trim back / prune any of the existing new growth off this old main trunk? All the new growth appears in about 4 locations along the trunk that I'm guessing at some point had branches coming out of it. They seem sort of knot-like. Some of those areas produced 1 new shoot, some upward of 4.
2) should i train all these new shoots to go straight up vertically toward the eventual arbor roof?
I've done some research online but I'm not sure what pruning 'system' I should do with this arbor idea and I am not completely clear on what 'parts' of the grapevine I'm looking at in this photo with the new growth, considering where it was cut in the old vine.
Thanks for any advice!