Hi @philgtaylor
Wow, what a vigorous and healthy vine you have!
I've grown both greenhouse vines and external vines over the year. I was only managing to get fruit on the greenhouse variety. Grape vines are super vigorous as you're experiencing. Lovely smelling textured leaves though that themselves can be used in cooking and preserves.
There are two different methods for pruning grape vines.
- Rod & spur - the method you've got essentially
- Guyot system - seen in vineyards where grapes are at 45 degrees to a wire support
There's so much advice out there on training new vines, which I'll skip over here. With a mature vine, my advice would be to prune back new growth to 5 leaves mid-summer to keep the vine compact.

Then in the middle of winter when the vines are dormant and leafless, trim back all side shoots to 2 buds ideally. Removing completely any side shoots that you don't want ie thinning out the vine. You can even alternate taking out every second side shoot on a very established vine like yours.
Once they have a framework it's about picking the buds you want to grow next season and removing/rubbing out any that you want to reduce/remove.

As they are so vigorous, you're only ever one season away from undoing any mistaken pruning, so don't worry too much. We always prune woodier laterals in the winter to stop the main woody trunk from bleeding necessarily and weakening the vine or causing disease. There's a guide for the basics of pruning below for any new gardeners reading this.
https://youtu.be/B47iplhJHkE
One tip I would give you is to make sure there's enough air to avoid mildew in that greenhouse and also allow light inside! So with the photo above, I'd look at removing 1/3 of all of that fresh leafy growth in early summer, ie nipping the leaves off at the bottom of their stalk in the early morning or evening.
Always use clean sharp secateurs as well.
Happy pruning and let us know how you get on!
Lee
Hi @philgtaylor
Wow, what a vigorous and healthy vine you have!
I've grown both greenhouse vines and external vines over the year. I was only managing to get fruit on the greenhouse variety. Grape vines are super vigorous as you're experiencing. Lovely smelling textured leaves though that themselves can be used in cooking and preserves.
There are two different methods for pruning grape vines.
- Rod & spur - the method you've got essentially
- Guyot system - seen in vineyards where grapes are at 45 degrees to a wire support
There's so much advice out there on training new vines, which I'll skip over here. With a mature vine, my advice would be to prune back new growth to 5 leaves mid-summer to keep the vine compact.

Then in the middle of winter when the vines are dormant and leafless, trim back all side shoots to 2 buds ideally. Removing completely any side shoots that you don't want ie thinning out the vine. You can even alternate taking out every second side shoot on a very established vine like yours.
Once they have a framework it's about picking the buds you want to grow next season and removing/rubbing out any that you want to reduce/remove.

As they are so vigorous, you're only ever one season away from undoing any mistaken pruning, so don't worry too much. We always prune woodier laterals in the winter to stop the main woody trunk from bleeding necessarily and weakening the vine or causing disease. There's a guide for the basics of pruning below for any new gardeners reading this.
One tip I would give you is to make sure there's enough air to avoid mildew in that greenhouse and also allow light inside! So with the photo above, I'd look at removing 1/3 of all of that fresh leafy growth in early summer, ie nipping the leaves off at the bottom of their stalk in the early morning or evening.
Always use clean sharp secateurs as well.
Happy pruning and let us know how you get on!
Lee