How to graft a jujube tree? An introduction to several grafting methods for jujube trees
Jujube, also known as Chinese date, is a deciduous small tree of the genus Ziziphus in the Rhamnaceae family. It grows in mountainous areas, hills or plains below 1700 m in altitude. Propagation is mainly by division and grafting, and some cultivars can also be grown from seed. Grafting jujube trees generally uses bark grafting, cleft grafting, side grafting and bud grafting. Let's take a look at the grafting methods for jujube trees!
Bark grafting
Bark grafting is a type of scion grafting and is best done after the jujube tree has sprouted, when sap flow is vigorous and the bark peels easily. This grafting method is simple, fast, and has a higher survival rate than other grafting methods. Choose a smooth spot on the rootstock and cut it off, then on one side of the cut surface make a small cut about 0.5 cm long from top to bottom through the bark down to the xylem, and peel the bark back to form a triangular opening. On the lower end of the scion, 2-3 cm from the bottom cut surface, cut downward at an angle with a knife to form a horse-ear shape, with the slope extending past the pith; on the opposite side of the slope, make another short cut 2-3 mm long at the lower end, forming a straight sharp point that makes it easy to insert under the bark. Insert the long cut surface of the prepared scion along the xylem into the bark through the triangular opening already cut in the rootstock (the long cut surface of the scion should fit tightly against the xylem of the rootstock), leaving 1 mm of the cut surface exposed above, commonly called "white showing," to promote callus growth. Then wrap the cut on the rootstock and the entire union with the scion tightly with plastic film so that no air can get in, and the graft is complete. If the scion has not been wax-sealed, wrap the scion tightly with thin plastic film.
Cleft grafting
Cleft grafting is a type of scion grafting, also called large grafting. It can be done earlier than bark grafting, when the bark is not yet easy to peel but sap has begun to flow. It can be used for grafting young seedlings in the nursery or for top-working large trees. For grafting young seedlings in the nursery, first clear away weeds and useless root suckers around the seedlings. Cut off the rootstock seedling close to the ground, then dig down about 10 cm of soil to expose the thicker, smooth part of the root crown. Cut the rootstock crosswise with scissors and split the rootstock lengthwise along the center of the cross section with a cut 2-3 cm long. Then quickly cut the scion from 2-3 cm above its lower end downward into a smooth double-sided wedge, thick at the top and thin at the bottom. If the scion is thinner than the rootstock, make one side of the cut slightly thinner than the other, with the main bud on the thin side. Then quickly insert the prepared scion into the split in the rootstock, leaving 1-2 mm of the upper end of the scion's cut surface exposed, commonly called "white showing," so that the cambium on the thicker side of the scion aligns with the cambium of the rootstock (if the rootstock and scion are the same thickness, align the cambium of the bark layers on both sides of the rootstock and scion). Then wrap the split in the rootstock and the union with the scion evenly and tightly with plastic film to help retain moisture. If the scion has not been wax-sealed, wrap the entire scion tightly with thin plastic film to prevent water loss.
Side grafting
Side grafting is also a type of scion grafting, and the suitable time for grafting is the same as for cleft grafting. When grafting, cut off the rootstock, then make an oblique cut into the rootstock along the cut surface, deeper than half the diameter of the rootstock but not more than 2/3, otherwise it is easily broken by wind, forming an oblique opening that reaches the xylem. The scion is cut basically the same way as for cleft grafting, except that the cut surfaces of the scion should be made with one side slightly longer and one side slightly shorter. When grafting, insert the prepared scion into the oblique cut in the rootstock with the long cut surface facing inward and the short cut surface facing outward, so that the cambium of the bark layers of the scion and rootstock align. The other steps and requirements are the same as for cleft grafting.
Bud grafting with wood
Bud grafting with wood is done in spring after sap flow begins in the rootstock. At a smooth spot on the base of the rootstock, use a budding knife to make a horizontal cut into the rootstock down to the xylem, about 1/3 of the diameter of the rootstock in length. About 1 cm below the cut, use the knife to cut a shield-shaped piece connected to the cut. Remove the wooden piece. It is best to use a scion similar in thickness to the rootstock. Make a horizontal cut with a knife 3 mm above the main bud, the same length as the horizontal cut in the rootstock, then cut a shield-shaped bud piece below the bud with the knife, the same size as the shield-shaped piece on the rootstock. Insert the bud piece into the shield-shaped opening in the rootstock and align the cambium of the bud piece with the cambium of the shield-shaped opening in the rootstock. Wrap tightly with plastic film strips, leaving the main bud of the scion exposed in the middle, and the bud grafting with wood is complete. If the scion bud piece is smaller than the shield-shaped cut in the rootstock, align the upper cut and the cambium on one side of the scion with the upper cut and the cambium on one side of the rootstock, then wrap tightly with plastic film strips, leaving the main bud exposed.
Bud grafting
1. Timing of bud grafting: Bud grafting is generally done in the growing season after the main bud has formed, using the current year's main bud, also called T-shaped bud grafting. If using last year's scion, bud grafting can also be done in spring after the jujube tree has sprouted. Because it is difficult to remove a bud piece with the complete vascular bundle, bud grafting with wood is generally used, also called chip budding. For rootstocks whose grafts have taken before July, the rootstock can be cut off above the grafted bud, and a mature grafted seedling can still grow in the same year. For rootstocks whose grafts have taken after August, the rootstock should not be cut that year, otherwise the grafted seedling will have difficulty overwintering due to its low degree of lignification; cut the rootstock before sprouting the following spring.
2. Collection of scion wood: Generally use the current year's jujube shoot, cut off the secondary branches on the main bud and the leaves on the main bud, keep the leaf stalks, then wrap well with a wet cloth to retain moisture and set aside. The collected scion wood should not be stored for long at room temperature; it should be used as soon as it is collected. If longer storage is needed, place it in a refrigerated container at about 5°C.
3. Grafting method: At a smooth spot on the rootstock, use a budding knife to make a horizontal cut down to the xylem, then cut a small vertical slit downward from the middle of the horizontal cut to form a T-shaped opening. To take the bud, use a sharp budding knife to make a horizontal cut about 3 mm above the main bud of the scion, reaching about 1/3 to 1/2 of the diameter of the scion, then below the bud about 1 cm from the bud, lift and cut upward to connect with the upper horizontal cut. Pinch the bud piece tightly with your hand and give it a gentle twist to remove the bud, then quickly insert it into the opening in the rootstock so that the horizontal cut of the bud aligns with the horizontal cut of the rootstock. Wrap tightly with plastic film, leaving the main bud and leaf stalk exposed. If after 7 days the leaf stalk is still green or falls off at a light touch, it means the grafted bud has taken; otherwise, graft again.
Jujube tree grafting methods and advantages
Jujube, I think most people have eaten it, soaked in warm water or liquor, used as an ingredient when cooking porridge, and so on. Of course, these can only be done after the moisture in the jujube has been dried out, but in fact the jujube is also a very nutritious fruit. However, what I want to tell you about next is not the jujube, but the jujube tree. Planting jujube trees actually involves a lot of knowledge, especially when using grafting, which has many points that need attention. Without further ado, let's get straight to the point.
The advantages of propagating jujube nursery stock by grafting are: First, it can maintain the excellent traits of the scion cultivar. This is because the scion is taken from branches or buds of superior mature trees. Its heredity is relatively stable, and variation generally does not occur after grafting. For example, the famous Zanhuang jujube and winter jujube are both grafted from wild jujube. After grafting, the difference between the fruit and fruit from own-rooted plants is small in fruit size and contents.
Second, it can bear fruit early. Because the rootstock root system is well developed, growth after grafting is vigorous and the branches are sturdy. This can turn slow growth into rapid growth. It can bear fruit earlier. At the Tianjin Jinghai Nursery, Shanxi pear jujube and winter jujube grafted on April 20, 1999 reached a seedling height of more than 1.5 m in the same year, with the tallest reaching nearly 2 m, trunk thickness nearly 2 cm, bearing 15-20 secondary branches with a length of 40 cm. Some trees bore fruit in the same year, and one retained pear jujube in the nursery produced as much as 2 kg of fruit in 2000.
Third, it can enhance the stress resistance of the jujube tree. Because the wild jujube used as rootstock has strong drought resistance and tolerance of poor soil, and wide adaptability to soil; if using local rootstock grown from root suckers or seedlings raised from seed of local small jujube or large jujube, it is already fully adapted to the local soil and climate conditions. This valuable adaptability and stress resistance of the rootstock have a good influence on the grafted jujube tree. Fourth, it makes full use of wild jujube resources. In the mountainous areas and plains of our country, wild jujube grows everywhere. Using wild jujube to graft large jujube is an effective way to speed up the greening of barren hills, barren beaches, hills and gully slopes and to expand the range of jujube cultivation. The working people of our country have a long history of using wild jujube to graft large jujube. To this day, in Zaolinping, Suide County, Shaanxi Province, and Beishuiyu Village, Fuping County, Hebei Province, old jujube trees grafted from wild jujube several hundred years old are still preserved and still produce a certain yield. After liberation, Shanxi, Shandong, Hebei, Henan, Liaoning, Gansu and other places all did a great deal of work in grafting large jujube onto wild jujube, and in recent years Tianjin also began this work in the mountainous area of Jixian County, all achieving remarkable results.
Grafting methods: The time and method of jujube grafting directly affect the survival rate of grafting and the growth in the same year. After several years of practice, the editor concludes: for spring scion grafting, grafting after the jujube tree has sprouted gives the highest survival rate and greater growth. Grafting too early will reduce the survival rate accordingly, while grafting too late will reduce the growth in the same year. In the Tianjin area, April 20 to May 15 is generally suitable. For bud grafting in the growing season, July to August generally gives the highest survival rate.
There are two methods used for grafting jujube trees: one is scion grafting; the other is bud grafting. According to the editor's research in recent years, for scion grafting, when both the rootstock and scion are relatively thick, side grafting is suitable, because it is easy to operate and also gives a high survival rate, and after the graft has taken there is no need to set up a support and tie it; when the rootstock is relatively thick and the scion is relatively thin, bark grafting is suitable; if both the rootstock and scion are relatively thin, cleft grafting is best. For bud grafting in the growing season, bud grafting with wood is most suitable.
Grafting technique: Different methods require different techniques, but one point is the same, and that is that the cambium of the rootstock and scion must be aligned and pressed tightly together. At the same time, if grafting nursery stock, the rootstock height is generally 10-15 cm, while for top grafting it depends on the specific situation.
① Side grafting: When grafting, first cut the scion into a wedge shape, with the two cut surfaces equal in length and width, the length depending on the thickness of the scion, 2-2.5 cm for thick ones and 1.5-2 cm for thin ones. Then according to the length and width of the scion cut surface, make an oblique cut into the rootstock about 1 cm from the upper opening, with a length and width basically the same as the scion cut surface, then insert the scion into the cut in the rootstock, preferably with all three sides aligned. If a beginner cannot align all three sides, at least one side and the upper bark layer (cambium) of the rootstock and scion must be aligned. Finally, tie tightly with plastic film.
② Bark grafting: (also called insert-bark grafting) It is suitable for root grafting, near-ground grafting and top grafting. The operation method is: first cut one side of the scion into a cut surface about 3 cm long, then cut another small cut surface about 0.5 cm long on the opposite side at the base and set aside. Then choose a smooth, branch-free side on the rootstock; use a grafting knife to make a vertical cut from the upper opening down to the xylem, about 2.5 cm long. After cutting, insert the prepared scion from top to bottom between the bark and xylem of the rootstock, taking care that the long side faces the xylem. The insertion depth should leave 0.3 cm of the scion's cut surface exposed above (white showing). Finally, tie tightly with plastic film.
③ Cleft grafting: First cut the scion into two symmetrical slopes, making it a wedge with a cut surface of 2.5-3 cm. The cut surfaces are required to be flat, smooth and clean. The bark must not lift, and at the same time the outer side left should be slightly wider than the inner side. Then use force to split the rootstock down the center from top to bottom with one cut. A depth of 2.5-3 cm is suitable. Pry open the split in the rootstock, insert the scion from top to bottom into the rootstock, taking care to align the bark layers (cambium) of the scion and rootstock and make them fit closely together. Finally, tie tightly with plastic film.
④ Bud grafting with wood: Bud grafting uses the main bud on the current year's growing shoot (new jujube shoot). During operation, first cut the secondary branches on the scion to 0.7 cm, then make a horizontal cut 1 cm above the main bud, reaching about 1/3 of the depth, then cut upward from 1 cm below the main bud, slanting through the horizontal cut, to form a shield-shaped bud piece with a flat top and pointed bottom, slightly with wood. Then at 10 cm above the ground on the rootstock, choose a smooth spot and use a knife to cut a "T"-shaped opening, with the horizontal cut 1 cm long and the vertical cut 1.5-2 cm long. Then use the knife tip to open the bark at the opening in the rootstock, insert the bud piece, align the upper end of the bud piece exactly with the horizontal cut of the rootstock, and finally wrap tightly with plastic strips from bottom to top, leaving the grafted bud exposed. After the graft has taken, cut off the rootstock shoot 1 cm above the grafted bud in late March of the following year.
Post-grafting management: Post-grafting management can directly affect the survival rate and preservation rate of grafting. Therefore, attention should be paid to the following three aspects. First, remove sprouts in time: after grafting by scion grafting and after cutting the rootstock on surviving bud grafts, the sprouting buds and branches on the rootstock should be removed at any time to ensure that nutrients are concentrated at the union, which not only effectively improves the survival rate but also affects the growth of the scion in the same year. Generally 3-4 times are needed. Second, untie in time: with the scion grafting method, when the new shoot grows to about 30 cm, it should be untied in time; a small knife can be used to cut the plastic film on the back of the graft to avoid hindering thickening growth. With bud grafting, it should be untied about 3 weeks after grafting to prevent damage to the bud graft. Third, set up a support and tie it. With the scion grafting method, the new shoot grows a great deal, generally reaching a height of 1-1.5 m in the same year, and has many branches, so a support is generally needed for protection to prevent splitting and breaking at the union, thereby causing losses. This is especially important for nursery stock grafted by bark grafting. The time for setting up the support and the first tying is generally immediately after untying, and the support is generally about 1 m long, inserted about 20 cm into the ground with about 80 cm remaining above ground. The second tying should be done when the scion grows to 60-80 cm.
Collection and treatment of scions: After many years of production practice, the editor believes that scions should be collected 5-10 days before the scions needed for spring grafting sprout, with April 13-18 suitable in the Tianjin area, and scions needed for growing-season grafting are best collected as they are used.
① Standards for collecting scions: For spring scion grafting, it is best to use 1-2 year old jujube shoots, with a thickness of 0.5-1.0 cm suitable, as too thick is inconvenient to handle when grafting. If there are not enough jujube shoots, sturdy 1-2 year old secondary branches can also be used, with a thickness of 0.3 cm or more preferred, as too thin will directly affect the growth in the same year. For summer bud grafting, the main bud on the current year's jujube shoot primary branch should be used.
② The method of cutting scions is: to make effective use of jujube shoots, when jujube shoots are used as scions, generally only one bud is left on each scion when cutting. When secondary branches are used as scions, 1-2 buds can be left depending on the length of the internodes. When cutting scions, the upper cut should be 0.5 cm from the bud. At the same time, it is best to store jujube shoots and secondary branches separately for use by category.
③ Treatment of scions: After cutting the scions, they should be treated promptly and stored well. The specific method is: after the scions used for spring scion grafting are cut as described above, they should be immediately soaked in clean water for 5-10 hours to allow them to absorb enough water, then taken out and air-dried. After the surface is dry, wax-seal them immediately. When wax-sealing, the paraffin temperature should be 90-100°C. The sealing speed should be fast, requiring completion within 1-2 seconds. After wax-sealing, immediately air-dry to dissipate heat or place in cold water to cool. After the scions cool, put them in wet gunny sacks, then store them in a cool place. If the grafting period is long and the number of scions is large, they should be stored in refrigeration equipment, generally at 1-5°C. The scions for summer bud grafting are the main buds on the current year's jujube shoot primary branch; after collection, immediately remove the leaves but keep the leaf stalks, tie them in bundles, then wrap them well with wet gunny sacks to prevent water loss, and it is best to use them as soon as they are collected.
In addition to using wild jujube as rootstock, grafted nursery stock all requires raising rootstock. According to local specific conditions, choose a place with good soil conditions, convenient transportation, sufficient labor, flat terrain, an irrigation water source, good drainage, and deep, fertile soil for the nursery site. Then irrigate the nursery site to build up soil moisture, prepare the land carefully, and plow and harrow thoroughly, striving for levelness. Generally apply 5000 kg of base fertilizer and 10 kg of urea per mu, spread on the ground, and plow 20-25 cm deep. Make beds and set aside. In rainy southern regions, use high beds, with the bed surface 15-20 cm above the ground. Make it lower for sandy soil and higher for clay loam to facilitate drainage. In northern regions with little rain, use low beds, with the bed surface level with the ground, and simply make bed ridges for irrigation. Generally the bed width is 80-100 cm. The bed length is 15-20 m, the bed ridge width is 30 cm, and the bed orientation is best north-south to allow the nursery stock to receive even light.
What has been introduced above are some methods and advantages of grafting jujube trees, as well as issues needing attention in post-grafting management. Ordinarily we only know how to "enjoy" the pleasure the jujube brings us, yet we do not realize that the growth of the jujube tree that nurtures it, gives it nutrients and brings it to maturity also involves so much knowledge. Through the above introduction, I believe everyone now has a general understanding of jujube grafting and will also be more interested in jujube. So why not get started and try it yourself right away?
Can jujube trees be grafted? How many years can a jujube tree live?
Jujube trees are generally planted more commonly in the north, and some people also plant them in the south, but not as commonly as in the north. Therefore, fruit farmers planting jujube trees should first understand the growth habits of jujube trees, as this is very helpful for planting jujube trees.
Growth habits of jujube trees
Jujube trees grow in mountainous areas, hills or plains below 1700 m in altitude. They are a warmth-loving fruit tree, with an average annual temperature in production areas of about 15°C. The temperature during bud break needs to be 13-15°C, during shoot and leaf expansion 17°C, during flowering and fruit set 22-25°C, and during fruit ripening 18-22°C. Jujube trees are fairly drought-tolerant and waterlogging-tolerant, but the flowering period requires relatively high air humidity, otherwise pollination and fruit set are unfavorable. In addition, jujube has a strong demand for light and is relatively sensitive to light, has strong soil adaptability, and tolerates poor soil and saline-alkali soil. But it fears wind, so when establishing an orchard, care should be taken to avoid wind gaps.
Can jujube trees be grafted
Hello, jujube trees can be grafted. The main grafting methods for jujube trees are the following three:
1. Side grafting: Take a scion that has already been wax-sealed and cut it into two opposing cut surfaces, with the long surface about 3 cm and the short surface about 2 cm. On the grafting site of the rootstock, choose a smooth side and use pruning shears to make an oblique cut downward, with the angle between the cut and the vertical axis of the rootstock at about 15 degrees, and the length of the cut similar to the long surface of the scion. Insert the scion into the cut in the rootstock with the long cut surface facing inward and the short cut surface facing outward, so that the cambium of the scion and rootstock align. Then cut the rootstock about 0.8 cm above the union, and tie the union and the cut top of the rootstock tightly and securely with plastic strips to prevent the scion from loosening and losing water. This method is simple to operate and gives a high grafting survival rate. The rootstock thickness should preferably be 0.7-2 cm.
2. Cleft grafting: Take a scion that has already been wax-sealed and cut it into two slopes of equal length, with the slopes 3-5 cm long. First cut off the upper part of the rootstock, trim the cut smooth, use a splitting knife or scissors to split the rootstock from the center, 5-7 cm deep, insert the prepared scion, align the cambium of the scion and rootstock, and tie the union tightly and wrap it securely with plastic strips. This method is suitable for thicker rootstock.
3. Bark grafting: Also called insert-bark grafting. Take a scion that has already been wax-sealed and cut the lower end into a smooth cut surface 3-5 cm long, lightly shave the back of both sides of the cut surface to expose the cambium, then cut a short slope 0.5 cm long on the back of the lower end of the long cut surface to make insertion easier. Choose a smooth spot and cut off the rootstock, trim the cross section flat. Make a vertical cut on one side of the rootstock with a small knife, reaching the xylem, and along the cut separate the upper bark from the xylem. When inserting the scion, face the long cut surface inward and the small cut surface outward, and slowly insert it downward along the cut line. Tie tightly and wrap securely with plastic strips. This method is suitable for thicker rootstock, that is, rootstock with a diameter of 2 cm or more.
How many years can a jujube tree live
As the saying goes, "a thousand-year turtle, a hundred-year jujube." So how many years can a jujube tree live? How many years does a newly planted jujube tree need before it bears fruit? According to the experience of Teacher Wang, a large jujube grower in Shaanxi, jujube trees can live more than 100 years, and under normal circumstances 20-30 years is no problem. If jujube saplings are grafted, they will bear fruit in 2-3 years; if saplings sprouting from the roots of jujube trees are used, they can bear fruit in 3-4 years; generally saplings sown from seed (jujube pits) need about 7 years to bear fruit.
In Nanshuiyu Village, Pingyang Township, Fuping County, there is a large jujube tree. The tree is more than 8 m tall, with a trunk circumference of 4.8 m and a trunk height near the ground of 1.9 m, covering an area of more than 70 sq m. According to research, this jujube tree was planted in the early Jin Dynasty, and has a history of more than 800 years. It still grows very vigorously and can produce more than 140 jin of fresh jujube each year. According to expert measurement, this is the oldest and thickest-trunked large jujube tree in the Taihang Mountains, and is praised as the "King of Jujube Trees."
Jujube tree pruning techniques
1. Pruning jujube trees is suitable in winter. In winter the jujube tree is in a dormant state, and there are many dead branches on the tree that should not remain. If they are not cut off in time, it is very unfavorable for the growth of the jujube tree the following year. Pruning jujube trees in winter will not have too great an impact on them because their reactions are relatively slow, and at the same time it can stimulate the growth of the jujube tree the next year. Second, jujube tree pruning can also be done in summer. In summer the branches of the jujube tree grow very vigorously. To avoid nutrient consumption caused by excessive branch growth, excessively growing jujube branches must be cut off. Only in this way can the high yield of the jujube tree be ensured.
2. Jujube tree pruning techniques need to follow some basic choices, such as the principle of "promote in the early stage, control in the later stage, block upward and release downward." Specifically, this roughly means that in the early growth stage of the jujube tree, that is, during the 1st-2nd years, try not to prune it, but once the jujube tree canopy reaches the height we want, we must carry out pruning control, that is, block the jujube tree from growing upward and appropriately guide the jujube tree to develop horizontally.
3. There are many pruning methods for jujube trees, and different pruning purposes use different methods. Common jujube tree pruning methods include propping branches, pulling branches, ring cutting, bundling, bud removal, pinching, bending and twisting shoots, and so on. Each method or means is for achieving a certain purpose. Jujube tree pruning technique is a relatively professional skill. It is not enough for us to know only some theory; we must also have some practical experience. The specific situation of each jujube tree will differ somewhat, and the methods we use are different. To learn jujube tree pruning techniques, we must fully combine the theoretical knowledge from books with our actual operations.
People living in the south may not see many jujube trees. The growth life of jujube trees is relatively long, and if a jujube tree bears a lot of jujube fruit, its income is also quite good, and the market demand for jujube fruit is also relatively high.