Have just planted a young grape vine in half an old wine barrel. Is there enough room for roots to grow?

We live inland Sydney Australia. Its now spring and we are trying to grow the vine to form a shade over our pergola in time for summer. Grape variety is Cardinal.

Have just planted a young grape vine in half an old wine barrel. Is there enough room for roots to grow?
Absolutely not. Grape vines grow very deep in soil. Eventually, their roots will grow so deep that a couple inches of rain on the surface has no effect on the plant. You'll have to put it in the ground to get any substantial growth from it.
Reply:I used to live in Mildura, Vic. I imagine that it has a very similar climate to Sydney. My friend had many grape varieties growing in wine barrels in their yard, they had been there for years and seemed to do well. You might need to check it out with your local nursery if you want definate answers.