Bougainvillea grafting is a common method for propagation and variety improvement. Below are detailed steps and precautions:
1. Grafting Time
Bougainvillea grafting is best done during the vigorous growth period, typically in spring (March-May) or autumn (September-November). During these times, the temperature and humidity conditions are favorable, which aids in wound healing and survival.
2. Preparation of Materials and Tools
Rootstock and Scion:
Rootstock: Choose a healthy, disease-free purple bougainvillea with strong vitality, as it is more likely to bloom after grafting.
Scion: Select semi-lignified branches from the current year with full buds. Retain 2-3 bud points and cut off half of the leaves to reduce water evaporation.
Tools: Prepare sharp scissors, utility knives, plastic film, raw tape, or adhesive tape.
3. Grafting Methods
Common grafting methods include V-grafting, T-grafting, and approach grafting.
(1) V-Grafting
Rootstock Treatment: Make a V-shaped cut at a suitable position on the rootstock, about 2-3 cm deep.
Scion Treatment: Cut the lower end of the scion into an inverted V-shape, matching the length of the rootstock cut.
Joining: Insert the scion into the rootstock cut, ensuring the cambium layers are tightly connected.
Securing: Wrap the joint tightly with plastic film or raw tape to ensure it is airtight.
(2) T-Grafting
Rootstock Treatment: Make a T-shaped cut at a suitable position on the rootstock, ensuring the cut is smooth.
Scion Treatment: Cut the lower end of the scion into a wedge shape, about 2-3 cm long.
Joining: Insert the scion into the T-shaped cut on the rootstock, ensuring a tight connection.
Securing: Wrap the joint tightly with plastic film or adhesive tape.
(3) Approach Grafting
Rootstock and Scion Treatment: Choose rootstock and scion of similar thickness. Cut the lower end of the scion into a wedge shape, about 2-3 cm long.
Joining: Insert the scion into the rootstock cut, leaving 0.3-0.5 cm outside the cut.
Securing: Bind the joint tightly with plastic tape.
4. Post-Grafting Care
Moisture Retention: Keep the grafted area moist but avoid prolonged exposure to rain.
Shading: Provide appropriate shading in the initial stages to avoid direct strong sunlight.
Observation: Regularly check the grafted area. If loosening or infection is detected, address it promptly.
Unbinding: Remove the binding material once the graft has successfully taken (about 1 month).
5. Precautions
Hygiene: Keep grafting tools and materials clean to avoid infection.
Compatibility: Choose rootstock and scion with strong compatibility. The closer the genetic relationship, the higher the success rate.
Standard Operation: Perform grafting quickly to ensure the cambium layers are tightly connected.
By following these steps and precautions, the success rate of bougainvillea grafting can be effectively improved, resulting in healthier and more beautiful plants.