When to Prune Southern Grapes
As a subtropical characteristic economic crop, the scientific pruning management of southern grapes directly affects fruit quality and yield. Properly mastering the optimal timing for grape pruning, combined with differentiated pruning techniques, can effectively regulate the distribution of nutrients in the vine, achieving high-quality and abundant yields.
Key Points Analysis of Pruning Southern Grapes
Optimal Pruning Period Selection
The best pruning period should be chosen between 20 days after defoliation and 15 days before germination (December to January of the following year). During this phase, the vine is in a dormant state, the risk of bleeding is low, and nutrients have been fully回流ed. Special attention should be paid to: 1. Areas south of 25 degrees north latitude can be postponed to mid-January.2. Early-maturing varieties should be pruned 10 days earlier.3. Pruning should be suspended during cold spells and resumed when temperatures rise above 5°C.
Detailed Explanation of Three-Level Pruning Techniques
Short Shoot Pruning (2-3 Buds)Applicable to varieties like巨峰 (Jùfēng), 夏黑 (Xiàhēi), etc., characteristics: • Retain 15-20 cm of the fruiting branch• Keep 40-45 buds per square meter of trellis area• Better results with the配套环剥促花技术 (matching ring stripping and flowering promotion technique).
Medium Shoot Pruning (4-7 Buds)Applicable to varieties like 红地球 (Hongdìqiú), key points:• Use a 45° diagonal cut to prevent water accumulation• Maintain a spacing of 20 cm or more• The top bud must be complete and plump.
Long Shoot Pruning (8-11 Buds)Operating norms for varieties like 克瑞森 (Kèrèsēn), which are strong-growing:• Adjust the angle with牵引绑蔓 (tension and binding of vines)• Keep 2 preparation branches per fruiting branch group• Need to配套摘心控旺措施 (implement measures like pinching the top to control growth).
Key Operation Precautions
• Maintain a safe distance of 1.5-2 cm between the cut and the bud• Use the double diagonal pruning method for branches thicker than 1 cm• Promptly apply healing agents to prevent disease infection• Implement分级更新修剪 (分级分级更新修剪) on weak trees.
By establishing a three-dimensional management system of 'time-variety-technique' and dynamically adjusting the pruning intensity based on the vine's condition, the yield of southern grape gardens can be increased by 15-20%. It is recommended to complement this with an integrated water and fertilizer system, promptly supplementing medium and trace elements after pruning to store sufficient nutrients for the growth of new shoots.