I have some 4-year-old Concord grape vines that are not completely upright and have a little bit of a curl to them from the weight of the vine not having being properly tied off. Is there a way to straighten them over time or should I just leave them as they are? They're producing buds / leaves / fruit and have lots of growth. I'm working on upgrading the trellis system which will help out tremendously I believe.
