What is usually used for grafting osmanthus
As one of the top ten famous traditional Chinese flowers, the grafting technique of osmanthus directly affects the growth momentum and flowering quality of the plant. Choosing the right rootstock not only improves the survival rate but also relates to key indicators such as later-stage stress resistance and flowering amount. This article elaborates on the compatibility characteristics of three mainstream rootstocks to help you master scientific grafting methods.
Core rootstock selection for osmanthus grafting
Practice of grafting on small-leaf ligustrum
The small-leaf ligustrum, which is closely related to the osmanthus family, has a genetic match rate of over 97%, and the success rate of cambium alignment can reach 85%. Its fast xylogenesis process is especially suitable for grafting operations in the rainy southern regions. It should be noted that the diameter of the rootstock should be 0.3-0.5cm thicker than that of the scion, and the grafting should be protected with a breathable film after completion.
However, this rootstock has the issue of slow root development, and it is recommended to perform root pruning every two years. Data shows that potted osmanthus grafted with small-leaf ligustrum has a delayed flowering of 2-3 years, with an average annual flower reduction of about 35%, and requires supplementary nutrition with potassium dihydrogen phosphate foliar fertilizer.
Application of flowing-silk rootstock in the north
In the north of the Yellow River Basin, the flowing-silk rootstock shows excellent cold resistance, allowing the osmanthus to tolerate -15℃ low temperatures. Although its unique male and female dioecious characteristics affect seed collection, a 95% survival rate can be achieved through bud grafting technology. Grafting should select robust flowing-silk seedlings with a diameter of over 2cm and an age of over 3 years.
Comparative experiments show that the flowing-silk rootstock can advance the flowering period of osmanthus by 20 days and increase the flower amount per branch by 40%. It is recommended to control the grafting height at 50-80cm above the ground to effectively prevent frost damage. It is necessary to promptly remove the rootstock buds to avoid nutrient diversion.
Other rootstock compatibility schemes
The water wax rootstock performs well in saline-alkali soil improvement areas, allowing the osmanthus to tolerate soils with a pH below 8.2. Although the growth is slow in the early stage, the compatibility is optimal in the later stage, especially suitable for rejuvenating old osmanthus plants. Recent experiments show that using the clustering ligustrum rootstock can increase the annual growth of golden osmanthus varieties by 25%.
Post-grafting management needs to grasp three key periods: avoiding rain and sun exposure in the first 15 days, gradually increasing sunlight after 30 days, and removing the binding tape after 60 days. It is recommended to use the 'double-cut embedding method', which improves the healing speed by 40% compared to the traditional split grafting method.
Choosing the rootstock should follow the 'three-look principle': look at the regional climate, look at the cultivation method, and look at the target variety. It is recommended to use flowing-silk rootstock for courtyard planting, small-leaf ligustrum for bonsai cultivation, and water wax rootstock for engineering seedlings. Combined with the correct grafting timing (March to April for spring grafting, September to October for autumn grafting), it can significantly enhance the ornamental value and economic benefits of osmanthus.