Grape vines grow quickly and are very productive so proper pruning and training is a good idea.
Grapes are more productive and less unruly with correct pruning and training. They are easier to harvest and grapes are larger, albeit fewer. Pruning doesn’t necessarily promote grape production, in fact they are usually quite prolific, so much so the overcrowded grape clusters are prone to diseases. Judicious pruning is beneficial, however they are tough little cookies and they are quite forgiving if you screw up.
Grape plants are vigorously growing woody vines that need support to cradle their stems and fruit clusters. Supports could be a fence, arbor or horizontal post system. A 6 foot fence is ideal but attach heavy duty wire horizontally along the fence for their tendrils to attach to. When grown on arbors they evoke images of a Mediterranean garden as the grape clusters dangle down from a leafy canopy, however they are difficult to maintain. Pruning and securing the plant is certainly more arduous as you need a ladder to take care of it.
A wire trellis is an efficient grape support. Sink sturdy posts into the ground 10 feet apart with intermediate posts every two feet, 5 feet above the ground. Run a 9 gauge wire between the posts horizontally, a couple of feet apart at the top. If you want two grape ‘arms’, add another 9 gauge wire lower down, about 2 feet above the ground.
When you first bring a grape plant home don’t prune it! Allow the plant to grow so it establishes a good framework and root system. The first pruning should be done during its first winter if it’s planted in the spring or the following winter if planted in the fall.
Select the sturdiest stem central stem that’s growing more or less upright to become the main trunk. Tie it to the main support. Once the main stem reaches the top wire, cut it back to two strong buds. Those buds will become the 'arms' reaching in opposite directions along the wire. As the buds develop into stems, tie them to the wire as they grow. If you have a two wire system, look for two strong stems that arise closest to the lower wire and tie them to their support.
Select the sturdiest stem central stem that’s growing more or less upright to become the main trunk. Tie it to the main support. Once the main stem reaches the top wire, cut it back to two strong buds. Those buds will become the 'arms' reaching in opposite directions along the wire. As the buds develop into stems, tie them to the wire as they grow. If you have a two wire system, look for two strong stems that arise closest to the lower wire and tie them to their support.
As the 'arms' grow, new shoots will appear along their stems followed by many grape clusters. If these side stems are not cut back, the grapevine will become a bushy crazy thing. There will be many grape clusters, but the grapes themselves will be small. Pruning off excess clusters in necessary if you want larger grapes. Yes, you’ll have fewer grapes but it will be worth it. Therefore, remove every third or fourth side shoots so the remaining stems are about a foot apart. Cut back any remaining side shoots to a couple of buds (nodes) on each of those side stems. They will become fruiting spurs and develop into grape clusters.
For mature and neglected grape plants, remedial pruning is often needed. Determine which stem is your main upright trunk and which ones are its ‘arms’. Select the most vigorous stems and remove all other growth. Then reassess and keep the main trunk and the horizontal arms; remove all other. Secure them to the support if they are not secure. Cut back all side branches that emerge from the arms to 2 to 4 buds. Once all the side shoots are cut back, thin the side shoots so they are about 10 to 12 inches apart.
Numerous grape vines are often needed to cover large arbors, pergolas and other overhead structure. Plant just one vine on each of the support posts or every other post. It all depends on the distance between the posts. Cut back the main stems to just beyond where you want the plant to branch out, approximately 2 feet off the ground. Remove all remaining side shoots.
When the main trunk starts to branch out, tie the most robust ones their support and remove all the others. For older grape vines, select the healthiest main stems. Save one or two main stems on each plant and tie them to their support, or twine the vines around their support. Remove all side shoots from the main stems to a 2 to 4 buds (nodes). If any of the main stems are long enough, guide them overtop the trellis and secure, if you can reach.
There are many methods of pruning grape plants, but this method is not too complicated and it works.
When the main trunk starts to branch out, tie the most robust ones their support and remove all the others. For older grape vines, select the healthiest main stems. Save one or two main stems on each plant and tie them to their support, or twine the vines around their support. Remove all side shoots from the main stems to a 2 to 4 buds (nodes). If any of the main stems are long enough, guide them overtop the trellis and secure, if you can reach.
There are many methods of pruning grape plants, but this method is not too complicated and it works.