I've used Vintner's Harvest blueberry, blackberry, and am currently making a batch of peach. For the blackberry I used 1 can and made a 5 gal. batch. I wanted a full-bodied wine but the she shop where I bought my supplies had only 1 can blackberry juice. They suggested I add a package of dried elderberries and top off to 5 gallons. (I don't recall the dried weight but the package was roughly the size of a baseball.) It made a very good batch of wine. If I make it again I will probably use less dried elderberries. I feel like the elderberries overpowered the blackberries in the wine.