Kitchen Garden Forum

Hello,
I have recently taken over an allotment and while digging a new bed in what appears to be the foundations of an old victorian greenhouse I have found a quite mature and very large grapevine (at least 12 ft long with many "spurs"). Asking around it appears this grapevine was planted outside the greenhouse and was then trailed inside where it grew quite vociferously. What can I do now to get some grapes on this vine? I can't build another greenhouse for a while so will it bear fruit outside? Is there anything I should be eeding it with? I'm guessing I can't prune it until winter. I would really like to save this old vine but have never grown grapes before so would appreciate any advice from experienced grape growers. Many thanks in advance.

Hi Tailfish and congratulations on your find.

I've only grown grapes in my garden and then usually against a wall. However I've often got enough grapes to make wine from (at least some of which has been drinkable).

My feeling is not to go out of your way to water and maybe not even feed it particularly this year, until you see how it does. Maybe others can advise if this seems incorrect?

Given the chance, many grapes will send out masses of growing points & eventually many branches. Whilst pruning of big branches should be avoided outside the winter period, I think it's fine to pinch out any excess growing buds with your fingers. Doing this on all bar 5-10 points may help direct most of the plant's energy towards useful leaf & fruit. Even then you may have to pinch out some excess later in the summer.

Finally some sort of support will be helpful. Some stakes either side of the main trunk with some stout wire running across will provide this. If you do a quick Google, you will find other sites giving better advice than mine, including guidance on how you can prune it to get a more structured growth next year.

All the best with your project. If you can, I'm sure people would like to see a picture - ideally before and after!!

We have a very mature grapevine in our greenhouse that is very productive.

We are quite harsh with it or it takes over completely. Once grape bunches have set we cut back all growth to just beyond a bunch of immature grapes.

We keep cutting back any new growth throughout the growing season. Leaves are also removed where they are shrouding the bunches. You may also have to restrict the number of bunches. We don't bother thinning the graps in the bunches as it is a nech aching job - we are conent to harvest small seedless grapes.

At the end of the season the vine is cut back severely just leaving short spurs from the main vine.

Lucky you to have such a find ! I echo the recommendations of the others in that you probably need to wait and see what happens to it this current season to find out what type of grapes it grows, etc. before taking too much drastic action. It's probably far too late now to do any drastic pruning as the sap will be rising and the vine will bleed badly. (I started to pruned mine back last week, having not pruned it back sufficiently last autumn and found it was already starting to bleed so have left it alone). Once it's growing vigorously and the grape bunches start to form, you can then trim back the surplus leafy growth back to the last little bunch as they do tend to go a little beserk in good growing conditions. Our vine is an outdoor Reisling and bears enough grapes to make a small quantity of wine each year although we've learnt to leave the grapes on the vine until late October or as long as possible to get the remaining autumn sun to increase the sweetness/natural sugar in them.
If you don't want the grapes for wine and only for eating, you may decide it's worth cutting some of the small bunches out to give the remainder a better chance to grow. I imagine few people have the patience to go over each individual bunch with a pair of nail scissors to cut out grapes from each bunch to allow bigger ones to form. It's a nice idea but probably impractical when there are so many other gardening tasks calling for attention.

I used to go over bunches with long bladed scissors but ended up with grapes everywhere! AND NECKACHE!

Just one comment - do not be afraid to prune once the sap is rising and even the buds are bursting.
The weeping does not do the vine any real damage - and some commercial vineyards deliberately prune late to delay bud burst to avoid frost damage.
The main problem with late pruning is mechanical damage - ie you knock off lots of shoots that will become this years fruiting wood.

If there is lots of tangled one year old wood I would be very tempted to cut this back to spurs with 2 -3 buds to produce this years fruiting wood.

then you should get some fruit that will in addition to the leaves help you identify the vine.
If you are really keen then the book to consult for leaf and tendril forms that help you identify the vine is Pierre Galet's 'A practical Ampelograpy' ... hope that helps.

sorry typo Ampelography ... missed out the 'h' !

Thank you for the link on identification, I also inherited an old vine and would love to identify it. Last year we had about forty plus bunches of grapes on the vine, they ripened late october and were delicious dessert grapes, the vine was just outside the greenhouse, I trained one leader into the greenhouse and that is in full leaf now with well developed small bunches of grapes on it, the outside vines are only just budding, next year I might train 2 leaders inside which should give us more early grapes, followed by later ones outdoors.

Natures Babe ... why not leave that leader you have trained into the greenhouse and spur prune it this winter, leaving this year's leader as the cordon ?
That way you don't have to keep training the new growth in and will get lots of new canes from the spurs to bear fruit in the greenhouse !
Just a thought....