It is well known that pruning is essential to the production and quality of grapes. There are numerous methods used to prune and train grape vines, but the philosophy is the same. Pruning prevents the vine from growing too much foliage, which in turn, amounts to not enough fruit. A well-pruned vine is given maximum exposure to sunlight, air circulation and maintenance.These factors create an atmosphere less likely to harbor diseases or pests. Knowing how to prune a grape vine correctly will increase your productivity and quality of the crop.
- Vertical Positioning System
Pictured here is the basic setup for a vertical positioning system, or VPS. In this system, the canes are secured to the guide wires of the trellis, and then the shoots are trained to grow upward, where they are tied. If you decide to use this type of system, be sure to choose the canes that are positioned well and are healthy. Then remove the others. This is the most common system to use for home grape growers, as it is simple and easy to understand.
There are some minor differences in timing and technique for various grape varieties, but generally, grapes should be pruned when the leaves have fallen, and the new buds have not emerged. Having the skeleton of the vine, without the leaf canopy makes it much easier to see the structure of your plant. Take your time as you learn the proper technique, and study the basic shape and growth patterns of your vines. Illustrated here are basic strategies for pruning your grape vines.
In spur pruning, this year's growth will have two fruiting canes that came from each spur. A spur was pruned last year to two nodes. To spur prune this vine, completely remove the cane that is the farthest away from the permanent cordon. The cane that is the closest, however, is pruned to two nodes, which will grow into next years spurs. From these spurs will grow the new fruiting canes. This is an example of one part of the vine, but there are many spurs all along the cordon, so there will be ample grapes produced.
- Spur and Cane Pruning
Using this method allows the vine to have a two year old cane, which produces many fruiting shoots during the growing season. There is also a spur with two canes growing out of it. When you prune this vine, you will completely cut off the two year old cane and most of the current years growth. When looking at the two canes coming from the spur, you will prune the one that is nearest the cordon, leaving only two nodes on the spur as replacements. The other cane, further from the cordon, is pruned shorter, but otherwise left alone. This cane will be next years two year old cane, and the process will repeat itself.
- Cane Pruning Basics