Grape Plant Grafting, Pruning, and Training
Today’s discussion is Grape Plant Grafting Methods, Pruning Procedure, and Training Information.
Grapes belonging to the Vitaceae family originated in Western Asia & Europe. Grapes are a non-climacteric fruit that develops on the perennial and deciduous woody climbing vine. Grape is a cross-pollinated vine with lobed, cut leaves with racemes of greenish flowers, the fruit consisting of fleshy pulp, stones, and skin, four-seeded.
Grapes can be eaten as fresh. Grapes used for making jam, juice, wine, seed extracts & grapeseed oil. Approximately 71% of world grape production is used for wine, 27% as fresh fruit, & 2% as dried fruit. However, in India, 90% of the grape is used for table purpose, even though wine production has made strides. The rest of the grapes are used generally for a raisin.
The propagation of grapevines is important in commercial viticulture & winemaking. Grapevines produce one crop of fruit each rising season with a limited life span for individual vines. Growers create that a grapevine that is grafted onto another root-stock produces a signature flavor that differs from the two original vines. The blend of the grape vines produces new & exotic flavors. Well, how do you propagate grape seeds? To grow grapes from seeds, set up by soaking the seeds in water for 24 hours. Then, put them in a plastic bag with damp paper towels & leave them in the refrigerator for 3 months. In the early spring, plant the seeds in small pots & give them up to 8 weeks to sprout.
Propagating Grapes from Hardwood Cuttings:
Hardwood cutting propagation is the most general process, though there are a select few types of grapes that cannot be propagated using hardwood cuttings, like muscadine grapes. You may be wondering how long does it obtain to grow grapes from cuttings? , a grapevine can take up to 3 years to make viable grapes, but that timeline is based on some environmental factors as well as how to care for the plant. Sunlight & well-drained soil are key to grape production, as is proper pruning. Each year during the dormant season, grapes must be pruned to ensure a healthy crop the following year. Grape vines can get leggy, and if the ratio of top wood to roots is high, then the roots will not be able to feed all the grapes. By pruning the vines, you ensure that the grapes produced are large, healthy & sweet.
The discarded cuttings from a single vine can be used to generate dozens of new plants each year. Cuttings 12-18 inches in length with three or more buds are taken from dormant plants in the fall or winter. These are stored in a cold, moist environment until the beginning of the growing season. Shortly before the beginning of the growing period, the grape cuttings are either calloused to induce root growth in rooting hormone & placed in the soil.
Keep the soil moist, and should see sprouts within a few weeks. Allow cuttings to get established and firmly rooted in pots before transplanting them outdoors in the early to mid-summer.
Propagating Grapes by Layering:
Layering means burying a portion of a recognized grapevine until it takes root. It’s a quick method to produce a few new vines during the growing season, and maybe the easiest process for the home gardener just wanting 2 or 3 new plants. Layering is used in a commercial setting to use a neighboring vine to replace a dead vine within a row.
Choose a parent grape plant & bend a young, still flexible 1 to 3-year-old vine near the ground level until it reaches the ground. Burry a portion of the vine beneath the soil, ensuring that you bury at least one node. The nodes are where new roots are probable to form when buried. Make sure that the end of the vine is left above ground to maintain growth.
Growing Grapes from Seed:
Grapes are normally propagated “clonally” so that they are “true to type.” Grapes can be propagated from seed, but they will not be like to the parent plant. Growing grapes from seed is an important tool for grape breeders & those interested in developing their own variety or grape.
Grape seeds can be collected from seed grapes, cleaned & stored in a moist paper towel or directly in the soil in the refrigerator for 3 months. After cold stratification in the fridge, the grape seed can be planted in the spring & will germinate into new plants.
Grafting method for Grapes:
Grafting is a procedure by which two grapevine plants are combined to create an improved single vine with new desired attributes. Grape vines can be grafted to either convert a vineyard to a grape varietal that is anticipated to receive high success or to remove a grape varietal for which there is no market interest. The grafting of vines is carried out because the roots of one type of grapevine might be better suited for a particular type of soil. You may have a question that why are grape vines grafted? Grafting a pest-resistant grapevine onto a less resistant vine can create the weaker vine stronger.
Time of Grafting in Grape Farming:
Trials have shown the best results with cleft & notch grafts are usually obtained by late grafting; that is, from early April to mid-April month.
Bark grafts are particularly prone to breakage since their mechanical attachment is poorer than either cleft or notch grafts. The ties must be particularly loose since the shoots greatly increase their diameter. One should know the purpose of grafting grapes, it’s reducing the size of fruit trees for small gardens & creating disease-resistant varieties of plants. Some growers graft two or more types of fruit onto one root-stock for gardeners to produce two or more varieties of fruit in a small space. The practice of grape plant grafting is completed in the early spring.
Different grafting methods for grapes:
Notch grafting is a more complicated grafting method & therefore has been little used on grapevines. It possesses the advantages of not leaving a deep, of not being affected by crooked grain, and placing the Scion better both in relation to smooth areas on the trunk & in respect to the desired position on the vine.
The notch is started with a saw cut about two inches down the side of the stock & about 3/4 inch deep at the top. Then one side of the saw cut is opened up with a blade to take out a wedge-shaped piece of wood.
The wedge is about 5/16-inch wide at the top of the cut & tapers to the saw cut both at the bottom and on the inside on top. The saw cut is generally made with a small curved pruning saw. Thus, the blade cut will not quite reach the extremities of the saw cut. In the beginning, the regular tendency is to make the knife cut too wide at the top. If this is done, it gets large diameter scion wood to fit. How wide the top cut could be depended upon the size of the scion wood. It is far simpler to work with large wood.
The scion is then cut with a taper similar to that of the stock & tapering quite sharply from outside to inside. The outside to inside taper of the scion must be slightly more acute than that of the stock so that the contact is completed in the cambial area. Again, as with cleft grafting, the scion position slants slightly from the top inward to ensure cambial contact. The scion is placed in the notch & pounded down with the handle of the grafting knife. The friction between the stock & Scion is sufficient to hold the scion tightly in place. In order to hold with friction only, the notch must be fairly deep as described. With shallow notches, the scions will drop out.
After grafting, cover with grafting compound & paint. While grafters untrained in the use of notch grafts are frequently reluctant to try this system, the extra skill required is generally gained within a few hours. The process is slightly slower, however, requiring about 20% more time than cleft grafting.
One or two-year-old grape vines may be whip-grafted at any convenient height above the soil surface. This process is used generally for vines too small for cleft or notch grafting, or too large for chip budding; that is, vines up to about 3/4-inch in diameter.
If scion wood can be created to match the understock, such a match is desirable. In many cases, the understock will be of increasing in diameter than the scion wood. If so, then the cambium layers are coordinated on one side only.
Depending upon the diameter of the wood involved, the sloping cut will generally measure from 1-1/2 to 2-inches in length. To provide greater rigidity, a tongue is cut in the stock & Scion, the cut starting about 1/4 of the way down from the point of the scion & stock. After being fitted together, the graft is wrapped with grafting rubber, then coated with the asphalt grafting compound & coated with latex paint. Since the understock is normally 1-year-old wood, and since the cambium layers of this type of wood become active earlier than that on the trunks of older vines, the grafting must be completed by the end of March.
This is carried out indoors during the late winter or early spring;
Prior to grafting, the cuttings are stored in damp sawdust and then soaked for 24 to 48 hours before the operation to make them less brittle. Cut rootstocks to 24 to 36 cm lengths with the lower cut instantly below a node Remove all buds, and align them in order of the diameter of the top Scions cut to one-node lengths with 2 cm above the node & 5 to 6 cm below. Align them over the rootstocks according to the diameter of the base Graft, either by hand or by machine. Dip top of molten paraffin wax up to just below graft union Store in crates, containing & sawdust. Maintain humidity at 90% and temperature between 21 to 29ºC for 3 to 5 weeks. Once callusing is complete, remove grafted cuttings & trim off any roots from the scion or shoots from the rootstock. Re-dip in molten paraffin wax. Transfer to cold store (1 to 4ºC) or plant in pots and keep at 18 to 21ºC for 7 to 10 days then moves to the temperate greenhouse.
Grafted rooted cuttings are either sold as bare cuttings that have spent one season in a grapevine nursery after grafting and so can be planted out within ten months of grafting.
Wants to know what is bark grafting? Bark grafting is a relatively easy & very successful method done in the spring after the bark begins to slip and the buds are opening. Bark grafting is perhaps the easiest method of grafting & requires the least skill. The bark on the trunks of older vines will not slip until late April month in the San Joaquin Valley. The actual date of possible grafting will vary with the variety & the year. It is basically a matter of testing to find the earliest possible date.
The bark does not slip in all places on the trunk at the same instance. Even though some bark may create slipping, the date for grafting may well come a week later before all areas will slip uniformly. After the top is cut off, the movable outer bark is removed from the grafting site. The scion is prepared first making a straight, but slanting cut about two inches long, generally on the side opposite the bud, and a cut on the opposite region about one third as long.
Hold the long cut of the scion against the trunk & slit the bark on both sides as wide as the diameter of the scion and as far down the trunk as the scion length. This bark flap is then peeled, left of the trunk remaining attached at the bottom. Roughly the top third to half of the flap is cut off (generally cut across while still on the trunk before peeling back). The scion is then placed against the trunk underneath the flap & two brads used to secure the scion, one through the back flap, and one during the Scion near the top of the cut off the trunk. 1-inch long, 18 brads will hold the scion. A staple gun can also be used.
Cover with grafting compound & latex paint. Results with this method have not been as always, good as with either cleft or notch grafting although equivalent at times. The cutoff area of the trunk does not cover over simply. The roots of grapevines go away deep into the earth. Amend to a depth of 24 inches to 36 inches with good organic compost or well-rotted animal manure to improve existing soil.
Read: Guava Grafting Methods.
How to Plant Grafted Grapevine:
Grape plants develop easily from cuttings. Select a healthy stem about two feet long with at least 4 buds. Place the cutting in fast draining, sandy soil in a place with full sun. Two buds must be below the ground and two above. The bottom half of the cutting must be dipped in rooting hormone. Early spring is the greatest time to plant from cuttings.
Plant from nursery stock by digging a gap as deep as the container. Prior to planting, soak the roots in compost tea for 20 minutes & dust roots with a mixture of 2 cups of kelp meal and 1 cup of bone meal. When planting, make sure that the top 1 inch of the root ball sits above the surface to stop sucker growth from the graft. Space the plants 6 feet to 8 feet apart.
Water young vines for the first 2 years during the summer. Water deeply & infrequently to encourage strong, deep roots. Give support for mature grape vines in the form of a trellis or fence. Vines can be trained to cover arbors & gazebos.
Apply organic fertilizers rich in nitrogen 2 weeks after planting. Reapply annually in early spring right before development starts. Do not apply nitrogen later in the season as it will delay ripening, inhibit coloring & create tender, late-season growth that will be damaged in the winter. Four to six inches of mulch may be applied to help control weeds & conserve soil moisture.
Pruning method is defined as “the elimination of plant parts to get horticultural objectives”. These objectives contain:
– Controlling the size and form of the grapevine.
– Optimize the making potential of the grapevine.
– Maintain a balance between vegetative growth & fruiting.
By this time, you would be thinking of what is the best time of year to prune grape vines? The best time to prune grapevines is during late winter, usually February month, while the vine is dormant & before growth begins in the spring. Grape vines must be pruned every year to stay fruitful. Any fruit clusters lasting on the vines all pruning waste must be removed from the vineyard through the dormant period & destroyed. All grape varieties make fruit on one-year-old wood. That means that the growth produced during the previous year will make fruit for the coming season.
Immature grapevines require abundant stems and leave to help develop a strong root system. The second year, select the strongest & most vigorous stem that developed during the first season. Remove all other stems & leaves as close to the base as possible. Stake the one remaining stem to give support. This stem will become the major trunk of the vine. Pinch the top of the major stem to encourage side shoots.
After the second year, select two of the best-looking stems that are rising horizontally from the main trunk. Ideally, they must be on opposite sides and about the same height on the trunk. Remove all other side growths. By the end of the second year, you must have a plant that looks like a ‘T’. This is now the essential frame of the vine.
Subsequent Pruning of Grapevines:
In early spring, select the better of the two original shoots to become the permanent trunk. Remove pruning method illustration the other one. Tie the young grapevine to a stake. As the grapevine grows, tie it to the wire. Cut it back right above where tie it. This promotes straight trunk development in the vine. Leave 4-6 buds near the top of the vine & remove the remainder. Remove any flower clusters from the increasing lateral shoots.
In early spring, select the 2 strongest lateral shoots from each side of the trunk. Cut them back to 5 to 7 buds and tie them to the wire, extending in opposite directions. Select two other canes, one on either side of the trunk & cut back to 2 buds. These are known as renewal spurs.
Grapes generate fruit clusters on canes that are two years old. They are non-productive after they fruit & should be pruned out. The four shoots that grow from the two renewal spurs on either side of the trunk are pruned. The strongest lateral cane on either side is pruned to 20 to 30 buds. These two laterals give you a total of 40 buds to 60 buds. The number of buds that retain for fruiting is determined by the vigor of the vine. When the grapevine is weak, leave no more than 40 buds. Retain 60 or more if the grapevine is vigorous. The other two shoots are pruned to 2 to 3 buds & they become the renewal spurs. So each year you are removing the fruiting wood from the previous year & selecting new shoots to become next year’s fruiting wood.
Prune in March month, so you can determine the amount of winter damage. Leave more buds after mainly harsh winters. Typically, 90 percent of the previous year’s growth is removed through dormant pruning. Ignore the heavy sap flow from fresh pruning cuts completed in late spring. This will not weaken or damage canes. The sap can cause contact dermatitis in some individuals. Wear gloves when pruning the vines.
What is Training? Training method can be defined as “the arrangement of plant parts spatially”. This is completed to develop a structure that:
– Optimizes the utilization of sunlight & promotes productivity.
– Adjust to the characteristics of the grape cultivar.
– Promotes efficient and sustainable vineyard management practices.
– Is economical to establish & maintain.
Training is an important method in grapes. It helps to maintain the stature & spread of the vine and facilitates the operations like pruning, inter-cultivation, spraying, and harvesting. There are several systems of training. All the auxiliary shoots are pruned & the main growing shoot pinched off at 15 cm, below the pandal level. Two shoots occur below the cut area are allowed to grow in the opposite direction on the wires overhead. These two shoots increase in main arms. On the main arms, side shoots are allowed to develop at regular intervals of 40 to 45 cm. These side shoots are called secondaries & tertiaries or canes from which fruiting spurs develop. The arms & secondaries form the permanent framework of the grapevine.
The total space allocated for each vine is covered in a gradual manner by intermittent pinching of the primary arms & secondaries, not allowing them to grow more than 60 cm at a time. As they grow, the shoots are tied with jute twine & all tendrils are removed.
Methods of pruning and training in grapes:
There are 2 basic systems of pruning. How you prune will depend on the individual grape variety you grow & which part of its canes can be expected to bear the fruitful buds.
Commonly used in the Concord & other American varieties, is best suited to vines whose canes are most fruitful at a considerable distance from the base. On these vines, fairly long canes are left for fruiting wood & only the wood that is retained for renewal is cut back short.
- Select the best-placed canes for renewal and cut them back to two buds each.
- Choose the best-quality canes for fruiting.
- Decide how many buds the whole vine must bear.
- Cut back the fruiting canes according to their vigor and size, & that of the vine.
- Eliminate the rest of the wood.
- Tie the grapevine to the trellis wire.
This spur pruning method is successful for most French hybrids since most of these varieties bear their most fruitful buds near the base of the canes. On these vines, all wood is spur-pruned or cut back to the short spurs for both renewal and fruit production.
- Choose the best-placed, most fruitful canes.
- Decide how many buds the whole grapevine should bear.
- Cut enough canes back to two-bud spurs.
- Eliminate the rest of the wood.
- Tie the grapevine to the trellis wire.
Read: Vanilla Farming.