Three years of winter pruning of grape trees
Winter pruning is a key link in grape maintenance, especially as three-year-old grape trees are in the transition stage of high yield. Scientific pruning can not only increase the fruit bearing rate in the coming year, but also enhance the plant's cold resistance. This article will systematically explain the three-year grape pruning specifications from the best time selection to specific operating essentials. Selection and preparation of pruning timing. The golden pruning period judges that 30-45 days after leaf fall is the best window period, and most of the northern regions are concentrated from mid-December to late January. At this time, the flow of tree sap slows down, making pruning wounds less likely to be infected with bacteria. Avoid extreme low temperatures below-5℃ to avoid frostbite incisions. Special pruning shears disinfected with alcohol are used for tool disinfection, and the edges are kept at a 15° angle. It is recommended to use three-sawing method for thick branches: first sawing the lower 1/3, then sawing the upper 2/3, and finally trimming the incision. Detailed explanation of the three-year grapevine pruning steps and shaping specifications for main vines. Keep 3-4 main vines as the skeleton, and keep the spacing more than 40cm. Use single-arm plastic surgery to cut off pest, insect and cross branches. Pay attention to retaining the 5cm protective pile at the base to avoid damaging the trunk cambium. Results The mother branch treated high-quality branches with a diameter of more than 0.8 cm left 8-12 short buds, and medium branches (0.6- 0.8 cm) left 5-7 buds. Use the "horse-ear-shaped" oblique shearing method, and the incision is more than 2cm away from the bud eye to prevent dehydration of the bud eye. Nutrient branch management retains 12-15 new shoots per square meter of shelf surface, and weak branches are cut off by sticking to the roots. Pay attention to keeping branch groups updated and replace 30% of the fruiting parent branches every year to maintain tree vitality. Key points for maintenance after pruning apply healing agent to the wound to prevent rot, and coat the trunk white to prevent freezing. Apply 5kg of decomposed organic fertilizer/plant, combined with calcium-magnesium phosphate fertilizer to enhance cold resistance. Irrigation is used to activate the tree before spring germination.
Through scientific pruning, the yield of grape trees can be increased by more than 20% in three years, and the number of buds retained per plant can be reasonably controlled to 60-80, which can not only ensure yield but also improve fruit quality. Remember the eight-character secret of "retaining the strong but not the weak, retaining the new but not the old" to help you cultivate a strong and high-yield tree.