I have a mature grape vice growing up my garage wall down an alley about 1 metre wide and 6 metres long. I'd like to plant a blackberry bush nearby and wondered how far apart I should keep them. Ideally, I would want the blackberry bush within abaout 20 inches so I can train it up a wall adjoining the garage but don't want to risk the vine in the process.
Hi Jerry, as it's a mature vine the roots will be spread over quite a distance (many metres) and happily growing under paths, patios etc. so I don't think you need to worry about the blackberry affecting it. If it was relatively young then it might be a concern but I'm sure you'll be fine in this case. Just take care not to cut through any thick vine roots (easily identifiable as they look just like the vine stem itself) when preparing the planting hole for the blackberry.