Being in front of a huge mass of vines and pondering what to do could be an intimidating encounter for the newbie or a skilled pruner. Be aware of two important suggestions:
Don’t be scared of cutting. When you finish, around 90% of the growth will be eliminated.
Grapes are strong and forgiving. Even if you commit a mistake, you’ll have the chance to rectify it the next time.
However, it is best to tackle your pruning with an attitude of learning and exploration, not a sense of panic. Grapes should be pruned in spring (February/March and early April) since if they are pruned too early, a hard freeze during winter may damage the buds and canes.
Starting Young Plants Off Right
If you receive your new grape plant, it will likely not be trimmed; instead, you’ll see a strong root system and many bare shoots that are rising from the top. When it comes time to plant in spring, it is recommended to reduce the amount of nodes down to one and reduce it up to 3 buds (Step 1). After planting the vine, it will begin to develop and will push out the new shoots. When the nodes measure 8-12 inches long, pick the most suitable one and help it grow by tying to stakes on the top and the bottom. It would be best if you looked for a strong growing shoot, either upright or close to it, that is coming directly from the old stem (not from the roots). Eliminate any other branches (Step 2.).
When the shoot begins to grow during the first season, continue tying it onto the stake to ensure it is straight and avoid breaking during the winds. The node will become your forever trunk and will last the duration of the vine. It is, therefore, important to ensure it is as straight and level as you can.
First Dormant Pruning
The first year’s vine should be able to grow at or over the first wire of the trellis (about 30 inches) during the previous year’s growth. If it isn’t, then cut it back to 3 buds and follow the same procedure as last year’s. This might seem extreme; however, it is important to establish a healthy trunk. The majority of species are vigorous and are able to reach the wire quickly. If your last year’s plant barely comes to the wire or is just a few inches above the wire, cut it from the bud’s first point above the wire. Tie the plant to the stake as well as the wire (A). If the plant is taller and you want to attach it with wire and stake. Cut the stem four or five buds above the tie, then bend the remainder of the shoot towards the wire to connect (B). The most vigorous shoots can go over the wire and may produce strong laterals on the sides. Pick the two laterals which have the closest proximity to the wire. Tie them to the wire, then cut to about three buds. Attach both the stems to wire as well as stake, and cut above the laterals to the sides (C).
In the summer, the new shoots until the next wire. After that, take out any new shoots that emerge from the root or the lower tree.
Pruning Established Vines
The grapes are fruitful on green shoots that grow from canes that are one year old. Pruning is the process of producing fruits in the current season, as well as the renewal of young plants to produce fruit in the coming year. The canes that were old and had fruit this year won’t have any more fruit in the future. There are a variety of methods to use when pruning grapevines that are established. Pruning with canes is the standard method in areas like ours, where the heat units might not be as high, and the vigorous vines may obscure the grapes. In this method, a permanent trunk is erected, and every year, new canes are picked from the top of the plant where the wire and chest meet. Two or three clubs from each side that are about 8-10 buds are harvested and connected to the wire, and the other canes are cut. Select clubs about the size of your finger, which are as close to the head as possible and have buds that are close to each other. Avoid large, big canes that are a bit too thick and have buds spaced from one another. Also, leave a couple of spur canes, which are trimmed to two buds. They will provide more clubs for the following year’s pruning.
The Kniffen pruning system is comparable to cane pruning in that the main tree has two levels: one at the wire’s lower height and another about 30” higher. Under our conditions, more often than not, the upper shoots grow so vigorously that they block out the lower levels, and thus, the Kniffen method is not often employed. Another technique that is sometimes used involves that of the cordon method. Certain wine grape varieties have better results when trained according to this method, but it is not advised for American varieties such as Concord. In the second year, each cane will be trained on either side of the tree, and they transform into permanent arms, which remain as the foundation upon which spurs of short length are planted to create new fruiting canes every year. The triggers are usually approximately two or three buds in length. In trimming a cordon-trained vine, there are times when it is essential to cut back excessive stimuli. Pick the motivation that is closest to the cordon’s arm, cut it into two buds, and then remove the remainder of the trigger.
Shoot Thinning & Training
In many regions with deep soils and a high nitrogen content, the grape vines are vigorous and generate excessive shoots. Even when the vines aren’t excessively vigorous, some shrinkage is often required to remove unproductive nodes that have no clusters of fruits or that are not spaced properly. This is known as the management of the canopy. The goal is to equalize the output of the vine as well as the amount of shoot and leaf growth.
Each grape shoot requires fourteen to sixteen leaves that are well exposed to fully ripen the cluster of grapes. If there are too many shoots packed together, the leaves are not able to receive enough light to enable photosynthesis. It is essential to ensure that all leaves receive adequate sun exposure because leaves that are shaded only perform at 6 percent of their capacity and might not contribute much to ripening this grape cluster.
Grape arbors are a great way to add shade and fruit to your landscape. With their vigorous growth, the grape plant will overshadow an arbor in just the course of a few seasons. For a consistent production of fruit, However, a bit of judicious pruning is necessary. The fundamental guidelines are the same, in the sense that you create an overall permanent trunk that runs upwards over the arbor with short spurs or laterals from which you choose the fruiting canes that are new every year. Suppose too many older non-fruiting and dead bats have been accumulated; cut about 50% of them off completely. In most cases, lots of sprouts of fresh shoots could develop in order to produce new clubs for next year.