[AlaninCarlisle]

For the very first time in my life I planted a black grape vine last year. It's made great progress and I now have two branches of it going in opposite directions along wires about 6ft high along the upper reaches of my polytunnel. Each branch is now about 8ft along its respective wire. There are also 3 bunches of grapes hanging down from the main stem before it splits into the two branches.

One bit of advice I read was to snip off and discard the bunches of grapes. Is this necessary? I also read conflicting advice about pruning the two branches. One was to remove one branch completely.

How do other members handle this situation?

[m1ckz]

i keep both going    an .when they have been harvested i just trim along both  branches   

[mjg000]

I have one on an allotment I am looking after over the summer for a friend.  There are numerous branches coming out in all directions and most branches have several bunches on.  yesterday I took off the branch coming straight out and trimmed back to where the grapes are growing in an attempt to get some sunshine to them.  have I completely messed it up?

[Goosegirl]

Have a look at the RHS website re- pruning grapes as there are various ways of growing them which dictates their pruning. Without looking at my RHS pruning book, Gigot springs to mind.

[New shoot]

I have one on an allotment I am looking after over the summer for a friend.  There are numerous branches coming out in all directions and most branches have several bunches on.  yesterday I took off the branch coming straight out and trimmed back to where the grapes are growing in an attempt to get some sunshine to them.  have I completely messed it up?

No, not at all    My vine is trained in a fan on a wall and I summer pruned it just the other day to remove the excess summer growth.  If you don't do this, the vine concentrates on growing rather than ripening the fruit.

There are various pruning methods, mostly linked to vineyards, but for a home gardener, the rod and spur method is the usual one used.  Its not a million miles away from growing cordon fruit trees.  You winter prune for shape and summer prune to maximise fruit production.  The RHS site does have info but so does the main site for this forum in the Grow Your Own section 

[Aunt Sally]

Oh, yuss...

http://www.allotment-garden.org/grow-your-own/grapes.php

[AlaninCarlisle]

No, not at all    My vine is trained in a fan on a wall and I summer pruned it just the other day to remove the excess summer growth.  If you don't do this, the vine concentrates on growing rather than ripening the fruit.

This is the bit I don't understand. I have two branches each about 8 ft long. Should I shorten these or just cut of the side shoots that are growing out of each branch?

[New shoot]

This is the bit I don't understand. I have two branches each about 8 ft long. Should I shorten these or just cut of the side shoots that are growing out of each branch?

I just did the side shoots.  I leave pruning back the main stems until the winter prune 

[AlaninCarlisle]

Thanks, and by how much do you prune back the main stems in the winter prune?

Just to reiterate the main stem goes from the ground to wires at about 6ft above the ground and then splits into two stems which are now about 8ft long and growing in opposite directions along this set of wires

[New shoot]

My vine is trained into a fan shape on wires, so its not very technical.  I just cut the main stems back to the ends of the fan shape.

I have seen vines trained right along the roof of polytunnels, so you could leave your main stems unpruned for a year or two and carry on going until you get the spread you want.

The main rule of thumb is that you winter prune for shape (i.e. the main structure) and summer prune for fruit, as it if the short spurs coming off the main stem that will produce grapes next year.  The other function of the summer prune is to stop the vine wasting energy on unwanted leafy growth and get light and air to the crop.

There are more technical ways of pruning that vineyards use, but you don't need to get into all that unless you particularly want to.  My vine is productive, but it is outside, so the crop sets late and the grapes don't get that big.  You should get good results in a tunnel