Grape Hardwood Grafting Time
In grape cultivation techniques, hardwood grafting is a crucial step to improve the success rate of variety improvement. However, improper timing control during the grafting process often leads to low survival rates. When is the best time for operation? This article will analyze the golden time window for grafting from a professional perspective and explain the key supporting management points.
Analysis of Grape Hardwood Grafting Time Nodes
Critical Half-Month Before the Flow of Sap
The 15-20 days before the start of sap flow in grapevines is the core operation period. At this time, the tree is at the end of dormancy, and the activity of the cambium cells gradually recovers. Comparative test data shows that the survival rate of grafting during this stage can reach 68%, which is 42% higher than during the peak of sap flow. In the northern regions, it is usually from late February to early March, while in the south, it can be as early as the end of January.
Standard Operation of Grape Hardwood Grafting
Key Points for Wound Treatment
Use a double-layer wrapping method: first wrap the interface tightly with elastic film, then add a waterproof tape on the outer layer. Special attention should be paid to leaving space for the bud eyes to be exposed, as tight wrapping can inhibit the formation of callus. It is recommended to add a rainproof cover before the rainy season to prevent mold formation at the interface.
Temperature Control Management Techniques
Implement micro-environmental control after early spring grafting: create a small greenhouse with double-layer transparent plastic bags to maintain a temperature difference of 25-28°C during the day and 15°C at night. Comparative observations show that the controlled temperature group roots 7 days earlier than the conventional group, with a 23% increase in survival rate.
Tool Selection and Treatment Standards
It is recommended to use tungsten steel grafting knives, keeping the cutting edge angle at 30° for best results. The knife should be disinfected with 75% alcohol before each cut, and the cutting speed should be controlled at 0.5 meters/second to ensure a smoothness of ≤0.2mm roughness. Experiments show that standard tools can improve the fitting degree of the cambium by 35%.