Probably difficult question to answer from a photo but does anyone have any idea what variety of grape this may be?
If it helps, the grapes have only one seed enclosed in the berry. The bunches are small but this could be down to age, location and/or pruning as I'm no expert
The vine is ancient (up to 50 years old - could be more) and grows in an unheated greenhouse with its roots spreading outside. I managed to propagate a new plant by taking a blind (no flowers) May runner up through an 8" pot with an enlarged hole in the bottom, adding about 1" of gravel then filling with compost (own mix, 60/30/10 organic compost/loam/crushed old mortar - not cement!) and staking it vertically. I severed it from the main vine in August, it's been doing really well and I've had to prune it back.
I would dearly like to know more about the vine, how to feed, prune and generally care for it because, apart from one book on the subject I've no practical experience. Should the bark be peeled off or left on? I did remove a lot of loose stuff last year but it seemed like taking lagging off a water pipe which is NOT what we do here with our winters. Also, how much leaf should be left on before the fruit starts to ripen?
The same greenhouse also has a small peach tree which bore about 12 fruits this year, very tasty but the stones split and the fruit went off very quickly. Basically all I did to it this year was to mist the leaves with water once the fruit was off the tree and it apears to be healthy.
Any other plants were removed from the greenhouse in January when the vine and peach were dormant and a sulphur candle was used for fumigation. Overwintering plants were then replaced after a couple of days and a good airing. Everything survived so I guess I did something right