I currently have grapes and blackberries growing in a hugel bed in my side yard, with strawberries and asparagus going in the main portion of the bed (30x5x2) and borage, garlic and tansy slated to go in for pest protection. I have limited growing space, but that bed has some room left behind the blackberries and grapes where there is a fence going up that would make a good trellis. I was hoping to plant something edible that would grow up the fence, but can't seem to find anything definitive on companion planting lists as to whether beans or cucumbers would be compatible with the blackberries and grapes I already have growing there. Is it safe to assume that I could plant beans or cucumbers up that fence being that they've not made the 'enemies' lists? Thoughts and input would be greatly appreciated.
Although I haven't tried the combinations you are asking about, I would think that beans (or another legume) would be a really good idea, because they would fix some nitrogen which would benefit your grapes and blackberries.
when you say this space is "behind" the grape and blackberry, do you mean in the shade? That could make a difference to what you put on the trellis. In my mind, the blackberry and grape would be on the trellis and you would be looking for something to grow around their feet. And if the trellis is on the sun side, planting it up is going to affect the grape and blackberry!