Grapevines are beneficial for their aesthetic beauty and delicious fruit harvest. The success of your grapevines, however, depends on many important things such as planting location and regular pruning. It is also important to choose a grapevine that is suitable to your region or climate. When growing grapevines, care for them properly to ensure they will provide you with an optimum harvest and beautiful appearance.
Caring for Grapevines
Choose a planting site for your grapes that is in full sun, preferably on a south slope with great drainage. Grapevines planted in partial sun risk contracting a fungal disease.
Prepare the soil that is already at the planting site (or around the grapevine already planted) by adding equal parts organic soil, compost and loam to make loose, fast draining soil. Try to amend the soil around 90 cm (3 feet) deep, since grapevines have deep roots.
Provide a method of support for the vine; this is commonly done with a trellis. The trellis or wooden stake needs to be installed into the ground right behind the grapevine, about 30 cm (1 foot) from the base. Trellising not only keeps the fruit above the surface of the soil where it is susceptible to rot, but it also trains the vines so they are easier to prune. Secure the main trunk of the grapevine to the main stake of the trellis with a plant tie. As the vine grows and matures, routinely tie more length to the trellis, aiming for the vine to grow out vertically.
Plant the grapevine if it isn't already planted. Turn the container the transplant is in carefully to the side and slide out the root ball. Carefully set it into the planting hole and backfill the soil up around the trunk of the grapevine. Water generously and let the soil settle so no air bubbles collect around the roots. Add another layer of soil on top if the soil sinks a couple inches.
Water the grapevines so the soil is consistently moist but not soaked. For the first couple weeks of the grapevine's life after planting, water daily. After this point, water a couple times a week, depending on your climate.
Layer mulch around the base of the grapevine in the summer to help retain moisture and protect the roots. Layer mulch around the base in the winter to protect from cold temperatures and to keep the roots warm.
Allow the young grapevine to grow during the first year with no pruning until its first winter. This will ensure that the grapevine develops a strong root system, main trunk (otherwise known as the cane) and lots of foliage. A grapevine is easier to prune after established foliage because you can understand the growth pattern.
Pick out the strongest-looking cane, or trunk, during the first year's winter season. Around this main stem, cut back all of the other stems to the base of the vine.
Determine the growing system of your grapevine. There are two basic growing methods: the four-cane Kniffen system and the six-cane Kniffen system. Many growers use the four-cane system since it is easier. This is where the main trunk has two of the strongest canes growing from each side of the trunk, equalling four branches that are supported on the trellis system by two horizontal wires. The six-cane system is similar to this, but has three branches on each side of the main trunk, being held by three trellis wires. Once you decide how you want to grow your grapevine, you can determine a pruning system.
Prune the grapevine depending on the system you chose. For four-cane systems, cut back to the four main canes. For the six-cane system, cut back to six canes. Before pruning, secure a brightly coloured ribbon to the strong canes that you are going to keep.
Allow the stems to grow out from the main trunk until the second year's spring season. At this point, cut back all of the side shoots from the main trunk, keeping the main four to six canes. Train the vine on the trellis to grow where you want it to. Do this by tying the larger vines horizontally on the trellis and pinching back any smaller branches.
Cut back the top of the grapevine's trunk during the summer season of the second year. Where you cut this depends on how high you want the grapevine to grow.
Continue to prune back all side growth from the grapevine's main trunk except for the main branches during the winter of the second year. This will help maintain the basic framework of the four to six cane structure.
Let the grapevine flourish during the third year's spring and summer seasons. Continue to lightly prune any excessive growth besides the basic framework.
Prune the main branches during the winter season of the third year to encourage fruit production for the fourth growing season. Cut back each main branch so there are 12 buds left on each, with each bud having one or two leaf joints (renewal buds).
Prune in this manner for the rest of the grapevine's existence. Each pruning season, allow one more bud to pop up and grow on the tip of the branch, after the other 12 renewal buds. This allows the grapevine to flourish longer and get stronger each year. This eventually provides more and more fruit harvest and makes it easier to train.