Vine plants add depth to any garden, climbing over fences, trellises and walls. Like many vining plants, ornamental grape vines will not necessarily assume an attractive shape and climb exactly where you want them to -- even when you've got all the necessary supports in place. If you want your garden to look neat and well-tended, properly prune all ornamental grape vines to keep them under control.
Prune ornamental grape vines while the plant is dormant, from late November to March. Late winter, January or February, is the best time for pruning.
Identify the best-looking, sturdiest cane on the vine. All other canes should be pruned away with sharp hand shears, cut down to the base.
Cut the top of the cane only if it is growing above the top of its support wire or structure.
Tie the top of the cane to its support using standard twine.
Cut away all the shoots on the cane except for three or four which are spaced widely apart.
Remove all flower and fruit clusters from the vine in its second year of growth to make the vine stronger. Many ornamental grapes don't produce fruit, but if you are growing fruiting types as ornamentals this advice applies.
Leave two to three canes on the vine during third-year pruning, cutting the remaining canes down so that only two to four buds remain on each.
Locate fruit-bearing canes after the ornamental grape vine is 4 years old, pruning away all other canes and growth. Trim the remaining canes until they have six to 10 buds.