[Justin]

Hi all, I planted a couple of grape vines in the poly tunnel this year. As we're on solid clay, they're in half barrels of suitable soil and have done well. the plan is just to grow them over the tunnel supports to the other side, no further, so there's two rods off each vine, one at each end of the tunnel. You can see them in the photos below, one going over the door and one along the first main support bar. There'll only go as far as the tunnel skin on the other side and then stopped at that point.

What I'm wondering is how to deal with them at the end of this first season. From reading, it seems you cut them back by ⅔ but that tends to be advice for outdoor grown ones on  a different training setup. I'm wondering if I should just leave them at the length they are, trim off all the leaves and leave them until the spring when I should drop them down so they get the sap evenly as it starts to rise before tieing them backup. I'd be looking to have these rods as long term growth with bunches off grapes just grown off these main rods.

Any thoughts on how best to deal with them as this seems to be a non-standard way of growing them.

[Possum]

There is some guidance below from the RHS.


https://www.rhs.org.uk/fruit/grapes/indoor-cultivation

My experience of grapevines is that they will grow and produce grapes however you prune them. So, to some extent, it is whatever is the most convenient for you. Some people say that you should put the pots outside during the winter as the vines need a period of dormancy. That would mean cutting back to the lower, woody growth and then tying in the soft new stems when they grow next spring. I tend to do this with my outdoor grapes and the are always smothered with fruit.

[Justin]

That's very helpful, thank you very much.