I've been growing Interlaken, Himrod, and Canadice grapes for over thirty years and have noted that Interlaken (my favorite for taste) has very poor productivity compared to the other two seedless grapes. I'm wondering if this is a normal characteristic of this variety or if my Interlaken vine has some kind of problem that affects its productivity. Has anyone on this forum grown Interlaken and noticed a similar lack of productivity? Thanks.