Methods for Rooting Elm Trees
As an evergreen species in the art of bonsai, elm trees are deeply favored by gardening enthusiasts for their unique branch and trunk shaping. Mastering scientific rooting methods not only improves the success rate of cutting but also lays the foundation for subsequent shaping and cultivation. This article will systematically analyze the complete process of rooting elms through three core stages.
I. Scientific Application of Rooting Hormone
1.1 Accurate Concentration Ratio
High-quality rooting powder needs to be mixed in a gradient of 50-200mg/kg, with a medium concentration of 150mg/kg recommended for spring and autumn, and reduced to 80mg/kg during the high-temperature summer period to prevent burns. The cutting should be made at a 45-degree angle to increase the absorption area before soaking.
1.2 Key Points of Time Control
Woody branches should be soaked for 30 minutes, while semi-woody branches should be reduced to 20 minutes. After soaking, they should be placed in a shady area to dry for 1 hour before transplanting, allowing a protective film to form on the cut.
II. Optimization of Substrate Ratio
2.1 Analysis of Substrate Ingredients
Decomposed leaf soil provides organic matter (60% of the proportion), river sand ensures breathability (30% of the proportion), and perlite enhances drainage (10% of the proportion). The three-in-one formula keeps the EC value stable at 1.2-1.8mS/cm and the pH value controlled at a slightly acidic environment of 6.0-6.5.
2.2 Sterilization Standard
The substrate needs to be sterilized by high-temperature steam or exposed to sunlight for 3 days to effectively kill nematodes and pathogenic bacteria. Before planting, water thoroughly with a 800-fold solution of carbendazim to establish a sterile environment.
III. Intelligent Environmental Control
3.1 Temperature and Humidity Management
Daytime temperature should be maintained at 22-25°C, and not lower than 18°C at night. Air humidity should be controlled at 70%-80%, using a timed misting system with each spray not exceeding 10 seconds.
3.2 Light Cycle Setting
Use a shade net with 50% shading, receiving scattered light for 4-6 hours daily. LED supplemental lights are recommended to use a combination of 450nm blue light and 660nm red light, with 2 hours of supplemental lighting daily to accelerate the formation of healing tissue.
Through the above systematic operations, the rooting period of elm trees can be reduced to 12-18 days, with a root germination rate of over 85%. It is recommended to water the roots with a 1000-fold solution of gibberellin every 7 days to stimulate the differentiation of secondary roots. After the new buds have 3 leaves, gradually increase the light intensity to complete the transition of hardening off.