What is the proper way to prune grapevines?

Question:

What is the proper way to prune grapevines?

Answer:

Grapevines produce fruit clusters on the previous season’s growth.  Before pruning, a grapevine may have 200 to 300 buds capable of producing fruit.  If the vine is not pruned, the number of grape clusters would be excessive and the grapevine would be unable to ripen the large crop or produce adequate vegetative growth. 

The purpose of pruning is to obtain maximum yields of high quality grapes and to allow adequate vegetative growth for the following season.

Timing to Prune

The most desirable time to prune grapevines is late winter or early spring.  In Iowa, pruning can begin in late February and should be completed by early April.  Grapevines pruned at this time of year may “bleed” heavily.  However, the loss of sap will not harm the vines.  

Where to cut

Going back to the upper wire, select two of the remaining four canes (one going in each direction).  Prune these canes back to 1 or 2 buds.  These short 1 or 2 bud canes are referred to as renewal spurs.  The renewal spurs provide the shoots or canes that will produce next year’s crop.  Prune the remaining two canes on the upper wire back to 8 to 13 buds.  The number of buds left on the fruiting canes is determined by plant vigor.  If the grapevine is vigorous, leave 13 buds per cane.  Leave only 8 buds per cane if the grapevine possesses poor vigor. 

Prune the four canes on the lower wire the same as those on the upper wire.  When pruning is complete, no more than 60 buds should remain on the grapevine.  When counting the number of buds on the grapevine, include both the buds on the fruiting canes and those on the renewal spurs.

Tools that will be needed

Tools required to prune grapevines include a hand shears, lopping shears, and saw.  Brightly colored ribbons or cloth strips can be used to identify fruiting canes and renewal spurs. 

Learn more in this article: How to Prune Grapevines in the Home Garden.

Last updated on
February 27, 2024