To prune, wait until the grapevines are dormant for the season, then identify and remove old growth that has already produced fruit. Trim off all weak or damaged canes, and trim new growth that has not yet produced fruit to promote new growth for next year.Continue Reading
Pruning should only be done when grapevines are dormant after they have lost their leaves. February or March is the perfect time to prune in most areas. Waiting too late to prune damages new growth and may impact grape production.
Grapes grow on the previous year's growth. Canes that produced fruit last year do not produce again, so remove this old growth with pruning shears or loppers.
Prune off all weak or damaged canes while the plant is still dormant. Weak canes cannot support growing fruit, and allowing them to remain on the plant while fruit matures my cause more damage to the canes. Any split or broken canes must also be removed.
To encourage grape vines to produce new canes for next year's fruit production, trim last year's canes back to five node spurs. Node spurs are recognizable by swollen areas where leaves and canes emerge. Make a pruning cut just above the fifth node on each cane.