How to Get Old Grapevines to Yield More Fruit

Well-pruned vines produce more usable fruit.

The best way to stimulate an old grapevine to yield more fruit is to cut it back. It may sound counterintuitive but an overgrown vine is overtaxed. A grapevine only has so much sap to go around. That sap is shared with leaves, vines and grapes. The fewer the stems and vines, the more energy the grapevine has for the grapes. Don't be afraid to cut the grapevine back severely. As long as you cut during the dormant season, the grapevine will bounce back.

Things You'll Need

• Pruning shears
• String
• Scissors

Instructions

1. Choose a main trunk. Old, overgrown grapevines may have several large-sized stems. Choose one and tie a string around it. Cut all other trunks of similar size back to their base.

2. Tie a string around two of the most robust canes on each side of the trunk -- four in total -- the trunk to mark them as keepers. Cut them back until there are only 10 buds on each cane. The prune will stimulate more vigorous growth next season.

3. Tie a string around two more robust canes on each side of the trunk -- four in total -- the trunk to mark them as keepers. Cut each of these canes back until there are only two buds on each cane. These buds will grow and fruit season after next.

4. Prune all of the other unmarked canes back to their point of origin.

Tips & Warnings

• Only prune when temperatures are above freezing.

• Annually prune any wood that is older than 1 year old. This will keep the grape vine growing vigorously. To encourage bushier growth, pinch off the growing tips of the remaining vines in spring.

• Healthy canes are reddish-brown in color and slightly larger than a pencil in diameter. Get rid of cracked, gray or unproductive canes.

References

• Orchard's Edge: Questions and Answers About Vines
• Grow Better Grapes: How to Prune a Grape Vine
• North Dakota State University Extension Service; Grapevines; Ron Smith
• Terry L. Ettinger Horticulture Consulting Services: Pruning Grapevines