Grapes should be pruned during the dormant season, late November to March. Since winter injury of fruiting canes will occur to some extent, late winter pruning generally is preferred. If pruning is delayed until near bud swell, the cuts commonly ooze sap abundantly. Some knowledge of grapevine parts is helpful in understanding pruning details. They are illustrated in Figure 3.
Mature plant shows parts.
The upper right portion is pruned to show a spur and fruiting cane. This is the main permanent stem of the plant. Immature, soft stem growths of the current growing season are shoots. Shoots arise from buds on wood one or more years old and bear leaves, flowers and fruit. These are the mature shoots, those which have become woody after growth has ceased.