How to Propagate Cornus officinalis by Grafting? A Detailed Guide to Practical Methods
Cornus officinalis is grafted within the species, with close genetic relationship and strong compatibility. After years of trials, the cleft grafting method has achieved a very high survival rate for Cornus officinalis grafting, and the technique is simple and easy to master. This method is mainly used for the renewal of Cornus officinalis.
(1) Collection and processing of scions
The mother plant used as the scion source must be a high-quality fruit type with large fruit, high bark yield, and strong stress resistance. Use one-year-old vegetative branches from the outer part of the canopy, and take care to keep them fresh after collection to prevent water loss. Before grafting, cut the scions into 10 cm segments with 1-2 pairs of buds, and make sure to collect and use them promptly.
(2) Cleft grafting method
Carry out the procedure in mid-to-late March, when the spring shoots begin to sprout. First, cut both sides of the scion flat at 4-5 cm from the lower end so that the scion takes on a wooden wedge shape. Then cut off the rootstock at 5-10 cm above the ground, making a single flat cut. At the cut surface, use pruning shears to split the rootstock from the middle, insert the scion, and align it from top to bottom. Leave the scion wound exposed 0.5 cm above the union, and tie and wrap the wound tightly and completely with plastic strips.
(3) Post-grafting management
1. Check survival status and re-graft
For grafted scions, after about half a month you can check whether they have survived. If the scion leaf buds unfold, the graft has survived; if the scion leaf buds are dried and shriveled, and fall off with a slight touch of the hand, the graft has not survived. For rootstocks and scions that did not survive grafting, if one grafting attempt failed and time permits, re-grafting can still be carried out.
2. Remove the binding material in time
Generally, about 20 days after grafting, the scion and rootstock can heal completely. After successful grafting, the scion grows and develops very vigorously. At this time, the binding material should be removed in time to prevent it from winding into the rootstock cortex and injuring the bud piece, which would affect survival.
3. Bud removal
After grafting, many sprouts often appear on the lower part of the rootstock. If they are not removed, they will affect the healing between the rootstock and scion and the later growth and development of the scion. In order to concentrate the tree's nutrients for the growth and development of the scion buds, the sprouts on the rootstock must be removed in time.
4. Strengthen water and fertilizer management
After the graft survives, strengthen water and fertilizer management, and carry out timely intertillage and weeding. During the overwintering period, apply 1000 kg of fully decomposed farmyard manure per mu to ensure the nutrient needs of the grafted seedlings.
(4) Nursery stock leaving the nursery
In the second year after grafting, the plants can leave the nursery and be transplanted for field planting before the spring shoots sprout.