Are you planting it in the ground or keeping it in a pot?

Hi Bamboo. Love your name. I have a big black bamboo growing in my garden. I'm going to plant the vine in a garden green potato sack, so, not in ground, but more of a pot.

Actually, the name Bamboo was accidental - that was my email address at the time and I put it in the wrong box when I joined!

If its not going in the ground, then water as you would any other container plant - when the surface of the soil is dry to the touch, give it a good soak (assuming there'll be free drainage from this potato sack, which hopefully there will be). In the ground, plants can put out their roots where they want to seek water and nutrients, but contained in something, they're relying on you to supply them.

Thank you all again for your great advice. I'm going to try and post some pics later.

Hi Kittt, it won't get any buds/ flowers this year. I have a Black Hamburg in a large pot inside a greenhouse. I bought it as a grafted stem in summer 2015. Had some leaves only later that year . The next year there were 2 bunches ,last year 4 bunches and this year it's loaded so have cut some out. All I do is follow the RHS grape vine care info. It specifies what to do in each year while its young. I scrape off the first inch of compost , add some slow release feed, top up the compost each spring, water well ( until water runs out of bottom) once a week or more if it's really warm and then enjoy the grapes in late August.

Note that grape vines will live for more than 50 years, and I wouldn't expect the sack to last more than 2 or 3. Best plan for a replacement! :)