First of all, the picking time of open-air grapes in winter
In the south and other areas, it is suitable to prune open-air grapes from 20 days after defoliation to one month before dormancy germination. In buried cold areas, it is advisable to prune grapes before they fall naturally to avoid frostbite of grape branches. In areas susceptible to late frost in spring, pruning should be done later, but before the bleeding period.
Second, the winter pruning methods of grapes
In winter, according to the yield and growth of grapes, we decide how many fruit branches to leave and control the number of fruit branches per unit area. The pruning sequence is from trunk to vine, from main branch to side branch, and then pruning the bearing branches. When pruning, the branches should be thinned first, then retracted and finally cut short.
Pruned branches should be robust annual branches, and the thickness should be about 0.8 cm. Thick branches should be kept long and thin branches should be kept short. Branches that have grown for many years should be retracted, and strong branches should be kept when pruning. If the strong branches are retracted for many years, the medium branches should be kept when pruning.
Sparse branches should be trimmed from the base, and the wound should not be too big, so as not to affect the growth of other branches. Pruning wounds in different years should be left on the same side of the main vine to avoid affecting the wounds, which is not conducive to the transport of nutrients and water by plants. Pruning and updating should be carried out every year to prevent the hanging fruit part from moving out and preventing baldness at the lower part of the branches.