How to Graft Osmanthus onto Elm Trees
Garden enthusiasts often wonder whether plants of different families can be grafted. Elm trees and osmanthus belong to the Ulmaceae and Oleaceae families respectively, with a distant genetic relationship, making conventional grafting difficult to survive. This article will start from the botanical characteristics to systematically analyze the feasibility of grafting and alternative solutions, providing scientific guidance for horticultural practice.
Feasibility Analysis of Grafting Elm and Osmanthus
Biological Restrictions due to Family Differences
Elm trees (Ulmus) and osmanthus (Osmanthus) have significant family differences, with unmatched xylem vessel structure and cambium activity cycles. Experimental data shows that the survival rate of grafting elms and osmanthus is less than 5%, and even if initial healing occurs, the plants will eventually die due to nutritional transport disorders.
Suggestions for Alternative Rootstock Selection
High-quality elm stakes can be grafted with plants of the same family: 1. Zelkova: closest relatives, with a cambium match rate of 90% 2. Rosaceae fruit trees: peach/ apricot/apple grafting survival rate is about 75% 3. Special treatment method: using bridge grafting technique can increase the survival rate by 15%.
Core Technology of Grafting Osmanthus
Rootstock Adaptation Scheme
1. Large-leaf ligustrum rootstock: use low-position grafting (10cm from the root collar), extend the joint surface with the tongue grafting method, and the joint wrapping needs to be maintained for more than 45 days. 2. Flowery cherry rootstock: apply NPK 15-15-15 compound fertilizer monthly, retain 3-5 main branches, and use the support and pull method to correct the stem proportion. 3. Water wax rootstock: extend the potting cycle to 3 years, add bone meal (20% proportion) to the base fertilizer, and implement ring stripping treatment in the second year after grafting.
Key Points for Scion Treatment
Select semi-woody scions, control the wax sealing treatment temperature between 58-62°C, and maintain the storage humidity at 75%±5%. The best grafting period is in spring when the average daily temperature is between 18-22°C, and a shade house with 50% shading rate needs to be set up after grafting.
Summary of Horticultural Practice
Grafting plants of different families needs to follow the physiological laws of plants, and it is recommended to prioritize the selection of the same family rootstock. For special shaping needs, a secondary grafting method can be used: first graft the same family plant onto the elm tree, and then graft the osmanthus onto it after shaping, but a double-layer transport system needs to be established. Mastering the three core technologies of rootstock selection, scion treatment, and post-care can significantly improve the success rate of grafting.