In article , Tom
Warner writes
We cut an old grape vine out of our conservatory last year, for various
reasons.
This year the stump, which ran outside, has grown 5 or 6 runners which I
would like to train up the outside of the conservatory. Should I concentrate
on one runner and cut the rest out or let nature take its course.
I don't know the variety, it's a black grape, quite sweet but with lots of
seeds. The position is south facing and sheltered, so frost damage should
not be a problem.

Select the best looking new stem to train on as a vine, and keep one
more growing as a fall-back in case you lose the first. A sweet black
grape is likely to be a bit tender for outside growing in UK, but it is
worth a try. Let the main stem grow on un-pruned next year, then expect
to cut side-shoots back to two fruit buds in following years. It may
form a few bunches next year, then grow on more vigorously later.

You won't lose the vine to frost, grape vines are more hardy than is
generally thought. It should grow healthily, flower and form up bunches
of grapes, but tender types will only mature to edible ripeness in the
very best of summers. Hardier varieties of grapes can be cropped in UK
and there are some commercial UK vineyards in favourable locations, but
varieties bred for indoor growing seldom crop well outside.
--
Alan & Joan Gould - North Lincs.