When is the best time to prune northern grapes in winter? How to prune them?

1. Winter pruning time

The timing of winter pruning of grapes must be well controlled. It should not be too early or too late, otherwise it will affect its storage of nutrients and will be detrimental to its germination and growth in the second year. The best time is 30 days before the tree enters dormancy to the sap flow period. If it is grown in a greenhouse, it should be done before covering the film. The specific time is between late October and mid-to-late November.

2. Pruning method

1. Pruning length: The specific cutting length during pruning depends on its growth, fruiting branch rate and the height of the flower bud attachment. Under the same conditions, strong branches with good nutritional status should be left longer, weak branches with flower buds should be pruned if they are well distributed, extension branches should be left longer, and preparatory branches should be pruned short. In addition, if there is insufficient fertilizer and water and the area is relatively dry, the main thing to do is to prune short.

2. Pruning position: The tissue at the cut position will be loose and water will easily evaporate. Therefore, when pruning, the cut should be about 2-4 cm away from the bud eye to prevent excessive evaporation of water, which will increase the number of dry branches. The cut should be on the opposite side of the cut bud.

3. The amount of buds left: The amount of buds left must be controlled, neither too dense nor too sparse. Usually the amount of shoots left is twice as much as in the spring of the second year. If there are 15-20 buds left on the new shoots on the trellis surface, then 30-40 buds should be left during winter pruning. If you are pruning short shoots, you should keep 8-10 fruiting mother branches.