The Best Time and Methods for Grafting Jujube Trees Explained in Detail

Jujubes, like grapes, hang on the jujube tree, and the clustered strings of jujubes are very lovely. As everyone knows, jujube tree cultivation is divided into two methods: division propagation and grafting, so what precautions are there for grafting jujube trees? Let us study together the relevant knowledge about jujube tree grafting.

Jujube tree grafting time and methods

The grafting methods for jujube trees include scion grafting and bud grafting. The best time for scion grafting is around the budding period, that is, April 15 — May 10. Grafting can begin when the spring temperature reaches 13-15°C.

Jujube tree grafting is mainly scion grafting, and scion grafting is further divided into cleft grafting, cut grafting, side grafting, bark grafting, and so on. Among them, the most widely used are bark grafting and side grafting, which are currently the most widely applied grafting methods.

Jujube tree grafting techniques

At present, jujube tree grafting in production generally mostly adopts bark grafting, cleft grafting, side grafting, and bud grafting.

1. Bark grafting.

It is a type of scion grafting and is suitable after jujube trees have budded, during the period when sap flow is vigorous and the bark is easy to peel. The grafting method is simple, fast, and the survival rate is higher than other grafting methods. The method is: choose a smooth area of the rootstock bark and cut off the rootstock, make a small cut about 0.5 cm deep from top to bottom on one side of the cross-section down to the xylem, and peel back the bark to form a triangular opening. At the lower end of the scion, 2-3 cm from the lower cross-section, use a knife to make a downward diagonal cut, forming a horse-ear shape, with the cut surface extending beyond the pith; on the opposite side of the diagonal face, make another short cut 2-3 mm long at the lower end, forming a straight sharp point to facilitate insertion into the bark. Insert the long cut surface of the prepared scion along the xylem into the bark from the already cut triangular opening of the rootstock (the long cut surface of the scion should fit tightly against the xylem of the rootstock), leaving 1 mm of cut surface above the cut surface, commonly known as "bai lu" (exposing white), to promote growth and healing tissue; then use plastic film to wrap the rootstock cut and the entire junction with the scion tightly, not allowing air to pass, and grafting is complete. If the scion has not been wax-sealed, use thin plastic film to wrap the scion tightly.

2. Cleft grafting.

It is a type of scion grafting, also called large grafting. The grafting time can be earlier than bark grafting, and it is carried out when the bark is not yet easy to peel but the sap has begun to flow. It can be used for grafting young seedlings in nurseries or for top-working large trees. The method is: for grafting young seedlings in a nursery, first clear away weeds and useless root suckers around the young 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 cross-section with scissors, and split the rootstock longitudinally along the center of the cross-section to make a cut 2-3 cm long, then quickly cut the scion from 2-3 cm above the lower end downward into a smooth double-sided wedge shape, thicker at the top and thinner at the bottom. If the scion is thinner than the rootstock, one side of the cut surface should be slightly thinner than the other, with the main bud on the thin side; then quickly insert the prepared scion into the split opening of the rootstock, leaving 1-2 mm of cut surface at the upper end of the scion cut surface, commonly known as "bai lu" (exposing white), 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, the cambium of the bark layers on both sides of the rootstock and scion can be aligned). Then use plastic film to wrap the rootstock split and the junction with the scion evenly and tightly to help retain moisture. If the scion has not been wax-sealed, use thin plastic film to wrap the entire scion tightly to prevent water loss.

3. Side grafting.

Side grafting is also a type of scion grafting, and the suitable grafting time is the same as cleft grafting. When grafting, cut off the rootstock, and along the cross-section of the rootstock make a diagonal cut into the rootstock as a split opening, with a depth exceeding half the diameter of the rootstock but not exceeding 2/3, otherwise it is prone to wind breakage, forming a diagonal cut reaching the xylem. The cutting method for the scion is basically the same as cleft grafting, except that the scion cut surface should be cut so that one side is slightly longer and one side is slightly shorter. When grafting, insert the prepared scion into the diagonal cut of 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 procedures and requirements are the same as cleft grafting.

4. Bud grafting.

Bud grafting is generally a method of grafting with the current year's main buds after the main buds have formed during the growing season, also called T-shaped bud grafting. If using last year's scion, bud grafting can also be carried out after jujube trees bud in spring. Because it is difficult to take a bud patch with the complete vascular bundle, generally woody bud grafting is used, also called chip budding. Rootstocks that survive grafting before July can have the rootstock cut above the grafted bud, and they can still grow into mature grafted seedlings that year. Rootstocks that survive grafting after August should not have the rootstock cut that year, otherwise the grafted seedlings, due to their low degree of lignification, will find it difficult to overwinter; wait until before sprouting the following spring to cut the rootstock. The T-shaped bud grafting method is: 1) 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 petiole, then wrap it with a wet cloth to keep it moist for later use. The collected scion wood should not be stored for long at room temperature and should be used as soon as collected. If longer storage is needed, it should be placed in a refrigerated container at about 5°C. 2) On a smooth part of the rootstock, use a budding knife to make a horizontal cut down to the xylem, then from the middle of the horizontal cut make a small vertical cut downward 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 1/3-1/2 of the diameter of the scion in depth, then below the bud at about 1 cm from the bud, lift and cut from bottom to top to connect with the upper horizontal cut. Pinch the bud patch tightly with your hand and gently remove it, take out the grafted bud and quickly insert it into the opening of the rootstock, align the horizontal cut of the grafted bud with the horizontal cut of the rootstock, wrap tightly with plastic film, expose the main bud and petiole, and bud grafting is complete. If after 7 days the petiole is still green or falls off with a gentle touch, it indicates that the grafted bud has survived; otherwise, regraft.

Management methods after jujube tree grafting

1. Remove sprouts, after grafting survives, check frequently and promptly remove the sprouts growing from the rootstock below the graft union, so as to concentrate nutrients and water for the growth needs of new shoots.

2. Loosen the binding, after the scion survives and the graft union heals, promptly loosen the binding and remove the plastic strip.

3. Set up support sticks, when the young tree grows to 20-30 cm, set up a support pole and tie the young tree to it to prevent wind breakage.

Management methods after jujube tree grafting: three points should be noted in management. First is removing sprouts; after grafting survives, check frequently and promptly remove the sprouts growing from the rootstock below the graft union, so as to concentrate nutrients and water for the growth needs of new shoots. Second is loosening the binding; after the scion survives and the graft union heals, promptly loosen the binding and remove the plastic strip. Third is setting up support sticks; when the young tree grows to 20-30 cm, set up a support pole and tie the young tree to it to prevent wind breakage.

Grafting methods for persimmon trees and jujube trees

Grafting persimmon trees must be fast, short in time, and skilled. Therefore, before grafting, full preparations must be made, and the items to be used should be placed within reach. This is because persimmon trees contain a substance called tannin, which is very easily oxidized in the air, forming a thin film that blocks cell exchange at the cut surfaces between the rootstock and scion, affecting survival.

The grafting methods for persimmon trees include bud grafting and scion grafting.

Above we have learned the relevant knowledge about jujube tree grafting techniques, and surely everyone has mastered it. There is no shortcut to grafting jujube trees; only by following natural laws and adopting correct and scientific planting methods can healthy jujube trees be cultivated and sweet, delicious jujubes be harvested.