After the seedlings are planted and germinated, only one healthy new shoot is left for each plant to extend and grow forward. When the new shoot grows to 30~40cm, the new shoot is set up and tied. In August, when the new shoot grows to 2~2.5m, the core is removed, and the top 2~3 secondary branches are reserved, and 2~3 leaves are reserved for repeated core removal, and the remaining secondary branches are reserved for repeated core removal. After defoliation in autumn, each main vine should be cut 1.5~2m.

2. Pruning from germination to fruit harvest

(1) bud wiping

When the buds germinate to the size of peanuts, the fine secondary buds on the bud eyes can be erased, and the hypertrophy of the central main bud can be preserved.

(2) thinning and fixing branches

When the new shoots grow to 3~5 leaves, keep the branches with strong growth and many inflorescences, and erase the branches with thin growth, no inflorescences or small inflorescences in time. Generally, two-year-old grapes can keep 5~7 new fruiting branches on each main vine, and the redundant new branches can be erased at any time. Perennial grapes should leave 10~ 15 new fruiting branches per square meter.

(3) Guidance and restraint

When the fruiting branches are about 30cm long, flatten the branches with strong growth potential to places with few branches and leaves, generally do not tie the weak branches, so that the fruiting branches are evenly placed on the shelf surface.

(4) Sparse inflorescence, pinching spike tips

Before flowering 10d or so, the thinning amount should be determined according to the number and size of inflorescences in the current year. Generally, weak branches leave no inflorescence, while medium branches leave one inflorescence. In years with few inflorescences, two inflorescences can be left with strong branches to ensure yield. You can grasp the spike tip according to the size of the inflorescence and pinch off all the attached spikes on the inflorescence.

(5) Choose the heart

When several grapes bloom in the greenhouse that day, 5-6 leaves are left above the inflorescence for fruiting branches and 4-5 leaves for nourishing branches. Only the topmost 1~2 secondary branches are left after the new shoots are cored, 2~3 leaves are left for repeated coring, and all the other secondary branches are smoothed.

3. The shaping and pruning of grapes planted for many years

In addition to the above methods, there are also the following requirements for shaping and pruning grapes that have been planted for many years:

(1) winter scissors

The grapes in the shed are mainly in the shape of dried dragons. Pay attention to keep the distance between the grape trellis and the greenhouse film at about 50cm. The spacing of fruiting branches on the main vine is not less than 30cm, and about 12 fruiting mother branches are left per square meter.

(2) Pruning of grapes after harvest

Immediately after the grapes are harvested, remove the plastic shed film, clean the shelf surface and remove the dense branches. When pruning in winter, the main branch is short branch pruning, leaving 2~3 buds.