Growing grape vines also means learning how to prune old grape vines for quality fruit production the following growing season. Each year, when the vines go dormant, the grape vines must be cut back to remove old growth and make way for new growth and fruit development. You will know when the grape vines are dormant because the leaves turn brown and start falling off. It is important to prune grape vines so that the quality of the grapes remains high.
Remove any dead leaves or fruit left hanging from the grape vines. Remove any debris and dead canes or leaves from the main trunk. Clearing the area helps to give a better view of what needs to be pruned.
Mark the grape vines with colored tape to clearly separate new growth from old. Cut back grape vines that are 2 and 3 years old or older. The previous season's growth produces the foliage and grapes for the next growing season.
Trim back all the grape vines to reveal two, four or six cordons.
Cut back the remaining cordons so there are six to seven spurs hanging from each cordon. Cut off the ends of the cordons about 6 inches from the last hanging spur.
Trim the spurs of the grape vines to leave at least five buds on each spur. Gather the loose vines in manageable bundles and tie with twine. Remove all trimmings and debris from the grape arbor. Fasten the grape vines securely to the growing system. Mulch the trunk of the grape vines with 6 to 8 inches of straw or 2 to 3 inches of sawdust to protect them from weeds and cold temperatures.