The Latest Technical Method Tutorial for Grape Cluster Elongation

After some grapes undergo berry-setting treatment, their fruit set is relatively large, which often makes later thinning work difficult; the mutual squeezing between berries leads to cracking, rotting and other symptoms, seriously affecting quality, so cluster elongation treatment should be carried out before flowering. So how should grape cluster elongation be carried out? Let's find out together.

1. The role of cluster elongation

Cluster elongation means elongating the cluster. It can reduce later flower and fruit thinning work and save considerable labor costs. After elongation, the tightness of the cluster can be reduced, which helps the berries enlarge, improves fruit quality, and avoids cracking and rotting. It can also increase the effect of light intensity on the flowers and increase the fruit-setting rate. In addition, after elongation the cluster has larger gaps, which helps reduce the prevention and control of pests and diseases.

2. Timing of cluster elongation

The degree of inflorescence elongation is related to the timing of elongation. If elongation is done too early, the cluster will become too long; if done too late, the effect will be insignificant. Generally, it is carried out when the new shoots are at the 6-7 leaf stage and the inflorescence has grown to 7-10 cm, that is, 20-25 days after bud break and about 20 days before flowering. Although cluster elongation has many benefits, it is not suitable for all grape varieties. For some varieties, after the cluster is elongated, uneven berries and stiff berries may appear, which instead increases thinning work. Varieties generally suitable for elongation include Red Globe, Beauty's Finger, Red Globe grape, and Summer Black, while varieties not suitable for elongation include Kyoho.

3. Methods of cluster elongation

At present, cluster elongation mainly includes two types: fertilizer and water management elongation and chemical elongation. Fertilizer and water management elongation is relatively safe, but it is slower, the effect is not obvious, and it is also greatly affected by temperature. Generally, about 15 days before flowering, water-soluble fertilizers such as urea, humic acid, and amino acids are applied by drenching. This method requires some practical experience. Applying nitrogen fertilizer before flowering carries certain risks, and differences in the environment of each region will also create differences. The use of fertilizer and water management for cluster elongation requires an average daily temperature of about 20-25 degrees. Chemical elongation has a fast effect and is relatively safe. It can generally be treated once the cluster emerges from the leaves and stopped 10 days before flowering. Commonly used chemicals include gibberellin, Bihu, and abscisic acid, among which gibberellin is used more often.

4. Precautions

When using chemicals for cluster elongation, pay attention to factors such as grape variety, tree vigor, tree age, and climate. At high temperatures, the concentration should be lower; at low temperatures, the concentration should be higher. For strong tree vigor, the concentration should be higher; for weak tree vigor, the concentration should be lower. After elongation, diseases should be prevented so as not to affect quality and sales, and for individual varieties, berry-setting work should also be done well.

The above is an introduction to grape cluster elongation techniques. We hope it can help you. If you want to learn more related knowledge, please follow us.