Our open-air grapes in the north will be ready to eat in a few days. Some of them have been colored recently, but they are still a bit sour when picked. Open-air grape cultivation is more susceptible to wind and sun, diseases and insect pests. Seriously, it is often seen that some large grape bunches start to rot from the inside, so they must be taken care of carefully, otherwise the work will be in vain and there will be no grapes to eat in the end.

As shown in the picture, the grape bunches are rotten from the inside, but the outside looks intact. It is possible that the grapes grow too densely, and the grape bunches are too large, resulting in poor ventilation. At this time, you need to pay attention to fruits and vegetables, and thin out about one-third of each bunch of grapes before and after the flowering period. This way, when the grape bunches grow up, they will not be so dense, and a certain amount of rot will be alleviated. At this time, you have to be reluctant to cut. This is called sacrificing the small to preserve the large. If you do not discard this part of the grape berries, the entire bunch of grapes will be destroyed in the end.

The second reason is infection by fungal bacteria and white rot.

At this time, you need to use scissors to cut off all the grape grains with diseases and insect pests, and then do not throw them directly under the grape trellis. Clean them all and throw them out far away. Then spray the remaining grapes with chemical liquid, such as Bordeaux mixture, thiophanate-methyl, etc.

The rot of the whole bunch of grapes is also related to the high temperature and rainy climate in summer. Grapes grown in the open air are usually placed directly in the yard. When it rains in summer and the high temperature evaporates, the grape vines become denser. It is not ventilated and can easily rot in a high temperature environment. Another thing you should pay attention to at this time is bagging the bunches of grapes. Although it may be a little troublesome, it is really effective in preventing grape rot.

The rot of grapes is related to many factors, and sometimes they are eaten by wasps.

However, when wasps eat, they usually pick out the larger, red and sweet grapes from the outside and do not eat from the inside. Grapes that have been eaten by wasps also gnaw holes into them, and then they begin to rot.

In short, if you are growing grapes in your own yard, the area is not very large. In order to have sweet and large grapes in autumn, you should thin them out quickly when they grow to the size of beans. Fruit bagging reduces grape rot.