graps pruning

Grapes: Pruning Techniques

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Pruning is one of the most important cultural operations in grape production because it regulates both vegetative growth and fruit production.
To properly prune a vine, you should know something about its growth and fruiting habit. The following image shows the major parts of a dormant vine after being pruned. This vine has been trained to the four-arm Kniffin system, one of several training systems used.

Pruning Terminology

  

The vines should be pruned during the dormant season, pre­ferably in March. Some things you must keep in mind are:
 

• The fruit is borne on shoots rising from one-year-old wood.
• The most productive canes are about pencil thickness (0.25-inch to 0.30-inch) and have an internodal length of five to eight inches between the fifth and sixth nodes or buds.
• The most productive buds are in the mid-portion of the cane; therefore, it is best to leave canes of 8 to 16 buds in length. Thin canes should carry fewer buds than thicker canes.
• To keep the fruiting wood close to the main trunk, leave one or two renewal spurs on or near each arm. (Cut back to short spurs leaving one to four buds).
• Prune the vine so you will maintain a balance between vegetative growth and fruit production. Where a vine is under pruned, (too many buds left) the vine will produce many small clusters of small grapes that may fail to ripen properly. If the vine is over pruned, (too few buds left) the yield will be low and the vegetative growth excessive. To "balance prune" a vine, the number of buds left is adjusted according to the amount of one-year-old wood removed in pruning.