What to do to increase the yield of grapes in a greenhouse
The editor answers related topics about grape cultivation in greenhouses for netizens on how to increase the yield of grapes in greenhouses, with specific content as follows:
What to do to increase the yield of grapes in a greenhouse
Grapes are crystal clear, juicy, sweet and sour, rich in nutrients, and very popular among consumers. Many farmers have grown them, and many of them are greenhouse-grown. As we all know, during the greenhouse grape cultivation process, temperature and humidity are very important and have a significant impact on the growth of grapes. So how to manage the temperature and humidity of greenhouse grapes?
Temperature management during the germination period of grapes
The effective accumulated temperature from warming to germination of grapes is 450℃ to 500℃. Generally speaking, the warming greenhouse starts from the first ten days of December, and the non-warming sunlight greenhouse starts from the first ten days of January. After 30 to 40 days of warming exercises, grapes begin to germinate.
If the indoor temperature rises too fast and too high, it is suitable for grape bud germination, while the ground temperature rises slowly, often leading to uncoordinated growth of the aboveground and underground parts, irregular germination, and poor development of small clusters. Therefore, the temperature in the greenhouse should be maintained at about 20℃ during the day and 10℃ to 15℃ at night during the first week after opening the curtain, and then gradually increased to 25℃ to 27℃. The maximum daytime temperature should not exceed 30℃. It should be kept at 15℃ to 18℃ at night. During this period, the humidity should be higher, and the air humidity should be around 90%.
Temperature management from germination to flowering of grapes
From germination to flowering is the period from the initial stage of main shoot growth to the period of vigorous growth. On the one hand, the new shoots grow, and on the other hand, the ears further differentiate. At this time, if the temperature and humidity are too high, it will cause the new shoots of grapes to grow too fast, affecting the differentiation quality of the organs of the fruit cluster, and then affecting the later fruit setting. High temperature and humidity during flowering can also cause the occurrence of gray mold disease. Therefore, the temperature and humidity of this period should not be too high. It is recommended to control the temperature at 25℃ to 28℃ during the day and about 15℃ at night, and the air humidity should be maintained at around 60%.
Temperature and humidity management during the flowering period of grapes
The flowering, pollination, and fertilization process of grapes requires higher temperatures. The pollen germination rate is highest between 27℃ and 40℃, and 32℃. When the temperature is lower than 25℃, most varieties are prone to poor pollination and fertilization, resulting in severe flower and fruit drop. Therefore, it is appropriate to control the temperature at 28℃ to 30℃ during the day and 15℃ to 18℃ at night.
The humidity during the flowering period of grapes should not be too high, otherwise it will affect the opening of the pollen sac and reduce the fruit-setting rate. High humidity can lead to diseases. However, low humidity can cause insufficient sticky fluid on the stigma of the pistil, which is not conducive to the development of the pollen tube and affects the fertilization process, causing flower and fruit drop. The humidity should be controlled at around 50% during this period.
Temperature management during the fruit expansion period of grapes
After the grapes are pollinated and set fruit, the young fruit enters a period of rapid expansion and growth. This stage requires a higher temperature, especially at night. Appropriate temperature increase is beneficial for the increase in fruit size, as the increase in fruit size mainly occurs at night. However, be careful to prevent the temperature from being too high during the day. When the inside temperature reaches 28 degrees, it is necessary to release air to cool down in time. At this time, the night temperature can be maintained at 18℃ to 20℃, and the daytime temperature can be controlled at 25℃ to 28℃. During this period, the external temperature and climate change剧烈. If the indoor temperature exceeds 30℃, pay attention to ventilation.
During the period of rapid growth of young grapes, the water demand is high, and it should be watered once a week or so. After watering, the air humidity will increase, and attention should be paid to the prevention and control of diseases by reducing the air humidity through ventilation to keep it at 50% to 60%.
Temperature management during the fruit ripening period of grapes
During this period, the outdoor temperature rises, the greenhouse ventilation time is longer, and the indoor air humidity is relatively low, which is conducive to the accumulation of sugar. On sunny days, the temperature of white weather can basically meet the temperature requirements of grapes. By mid-May, all windows in the greenhouse can be opened, and the base film can be opened in the greenhouse. The temperature should be maintained between 28℃ and 30℃ during the day and 15℃ to 20℃ at night. The indoor and outdoor air humidity is basically the same, about 50%. However, when it rains outdoors, the ventilation windows should be closed to prevent outdoor moisture from entering the room, increasing humidity, and causing disease breeding and fruit cracking.
Temperature management during the dormancy period of grapes
When the temperature is lower than 10℃, the grape leaves turn yellow and the leaves fall rapidly, indicating that the grapes have entered the dormancy period. After defoliation, there should be a low-temperature stage below 7.2℃ to allow grapes to go through appropriate low-temperature exercises and fully complete dormancy. Generally, after winter, the greenhouse can be closed and covered with straw curtains to prevent the greenhouse temperature from rising in the sunlight. After the end of December, the curtain is opened to raise the temperature.
The above is the management of temperature and humidity in greenhouse grapes. The requirements for temperature and humidity at different stages of grape growth are different, so growers should manage according to the growth of grapes. Mastering the key points of temperature and humidity management is the foundation for high yield of greenhouse grapes. I hope the above content can be helpful to grape growers.
The above is the knowledge of how to increase the yield of grapes in greenhouse greenhouses. I hope this article can bring you a little help after reading it!