When to Prune Southern Grapes
In the warm and humid southern regions, grape growers often face pruning challenges. Scientific and reasonable pruning not only adjusts the distribution of tree nutrition but also improves fruit quality and yield. Mastering the correct timing and methods of pruning is a "required course" for every grape grower.
Golden Time for Pruning Southern Grapes
Winter Dormancy Period Pruning
The best pruning period is 20 days after defoliation to 15 days before germination, when the flow of sap slows down and wounds heal quickly. Pruning too early weakens the plant's cold resistance, while pruning too late can cause bleeding, leading to a decline in tree vigor. It is necessary to avoid operations during consecutive rainy and cloudy days.
Summer Supplementary Pruning
During the peak growing season (May-July), it is necessary to remove excess buds and thin out dense branches to ensure ventilation and light. Focus on dealing with vigorous branches and competing branches to avoid ineffective nutrient consumption.
Detailed Explanation of Three Pruning Techniques
Short Shoot Pruning Method (Retain 2-3 Buds)
Suitable for European and American hybrid varieties such as Jufeng and Xiaye. Retaining the base healthy buds can promote the renewal of fruiting branches. The cut should be made at a 45-degree angle to ensure a smooth cut without burrs.
Medium Shoot Pruning Method (Retain 4-7 Buds)
Preferred for varieties such as Hongdiqiu and Victoria. Retain medium-length fruiting branches and combine with arch-shaped binding to improve fruit setting rate. Note that the diameter of the retained branches should reach 0.8 cm or more.
Long Shoot Pruning Method (Retain 8-11 Buds)
Suitable for vigorous varieties such as Keresen and Meirenzhi. Adjust the angle of the branches with the support structure and maintain a 60-70° angle for binding. It is recommended to retain 12-15 fruiting branches per square meter of trellis area.
Key Operation Precautions
Pruning Cut Treatment Standards
The pruning cut should be 2-4 cm away from the bud and use the "horseshoe" pruning method to avoid accumulation of water. Large wounds need to be coated with a healing agent to prevent bacterial infection.
Tool Disinfection Management
Disinfect pruning shears with 75% alcohol before each pruning and repeat disinfection between different plants. Diseased and weak plants should be pruned last to prevent cross-contamination of diseases.
A scientific pruning system needs to be combined with water and fertilizer management to achieve maximum benefits. It is recommended to apply organic fertilizer promptly after pruning and combine with foliar calcium fertilization to strengthen tree vigor. Mastering these core technologies will ensure consecutive years of high yield and quality of southern grapes.