Pruning/training a Greenhouse Grapevine

So after trying for several years to grow concord and other cold hardy grapes outdoors here, with little success (a couple of bunches total); I bit the bullet and put a concord vine in my greenhouse. It is planted in the ground and my plan was to train it up to a steel I beam which runs the length of the GH, at ~9-10’ up from the ground. (I will hang some steel cable from the I beam for the vine to spread horizontally up there)

Last year it grew OK (given that it got a late start) and made it 6’ up from the ground. I did not do any dormant pruning as I wasn’t sure how well it would overwinter. Well it has started growing now, with some of the buds lower down 1’ long already. It is probably past time to do some pruning/training.

So I was wondering a few things:

Is training it up to a 9’ height before branching a realistic thing to do for grapes? I have a neighbor who has a grape in her GH and did a similar thing but the beam in her GH is only 6’ up or so.

What would the best pruning/trimming “plan” be for getting my vine up there to branch out? I assume I should head off or cut back the lower horizontal branches, but how severe should I be? I don’t mind a lower horizontal or two while it is growing up to 9’ say for a year or two (especially if I might get some fruit from them), but I really don’t have room for much long term horizontal growth until the vine is further up. Ideas?

TIA

Sure is. Mine are trellised at about 8.5ft. Right now you just need to grow a trunk up to the trellis. Then train it around wherever you need it. If it grows enough this summer, and it should, you can leave a small crop next

yr.[quote=“Steve333, post:1, topic:5193”]
What would the best pruning/trimming “plan” be for getting my vine up there to branch out?
[/quote]

It doesn’t need to branch out this year. One cane 4-6ft long would be enough to crop next summer. The following yr it will have all those canes that fruited the prior yr and you can leave as many canes as you want.

Here are some pictures of my greenhouse grapes during their second leaf, one yr from planting.

<img src=“//growingfruit-images.s3-us-west-2.amazonaws.com/original/2X/6/6c2b2dd339062b578dfeb3c781ddf167cf0d7f01.JPG” width="750"height=“1000”>

4 Likes

Those look excellent Fruitnut!

Oh sigh. . . I’ll never see anything like that. You are something else!

1 Like

Thanks @fruitnut. Very impressive, I hope I can do half as well.

So, for a rank beginnner at grape pruning (my outside ones barely survived and never got to the pruning stage), what technique would you recommend?

Should I take off the lower branches completely? Leave a few leaves on them? If you have time, some general guidelines on what to take off and when would be appreciated

I’d force it to grow up where you want it by cutting off everything down low. Get as much growth on the trellis as possible this yr. You can allow a few bunches as soon as the cane or canes size up to 3/8 inch or bigger.

1 Like