Grape pruning is important because when grapes are not pruned vines become very dense, diseases become hard to control, and fruit quality declines. Grapevines require yearly pruning.

Pruning is not difficult and can be done anytime during the dormant season. The goal of pruning is producing an optimum crop. The more buds left at pruning, the more fruit will develop. However, if too many fruits are left on through the season, fruit will be small and, even worse, may not ripen.

As a general rule, big vines grow more buds and therefore more fruit than small vines. Keep new growth on the vines near the center of the vine. Harsh winters occasionally damage trunks; new trunks (renewals) should be selected from the suckers growing from the base of the vine. For some varieties this must be done every year and as many as four trunks of different ages left during the growing season.

When pruning, leave just enough vine to allow it to grow to fill the space allotted along the wire (about 8 feet long). The crop can then be controlled by fruit thinning to no more than one cluster for each rapidly growing shoot.

Fruit thinning is frequently necessary to assure maximum quality and ripening. It is possible (and often necessary) to control excessive cropping by removing fruit during the growing season. The earlier this is done the more effective it will be. To obtain large berries and large clusters, remove small or imperfect flower clusters as soon as they appear.

For detailed information on pruning and other aspects of growing grapes, see Cornell University Cooperative Extension's fact sheet.

For tips on a variety of gardening topics, see our Plant Information Guides.
- Courtesy of NYBG Plant Information Service