Five management measures for achieving early maturity, high yield and high benefits in greenhouse watermelon

    Greenhouse watermelon cultivation is highly technical and belongs to intensive, refined cultivation. Only by adopting comprehensive and coordinated measures when growing watermelon can the goals of early maturity, high yield and high benefits be achieved.

Greenhouse watermelon

    1. Regulating the temperature inside the greenhouse.Within 5-7 days after the watermelon seedlings are planted, attention must be paid to raising the soil temperature. When the daytime temperature is above 35°C, measures should be taken to shade and cool the greenhouse. The nighttime temperature must not be lower than 15°C, and the greenhouse temperature can be controlled by opening and closing the skylights. When the watermelon vines grow to about 3 cm, the small arched tunnel can be removed. During the full flowering period of greenhouse watermelon, sufficient light and a relatively high nighttime temperature should be maintained. When the outside temperature exceeds 18°C, ventilation should be increased, with the skylights and both sides of the greenhouse opened at the same time for ventilation, keeping the daytime temperature inside the greenhouse below 30°C, to prevent high daytime temperatures and excessive day-night temperature differences from causing a decline in watermelon flesh quality and spoilage.

    2. Pruning and vine pressing.Each watermelon plant should retain only 1 main vine and 2 side vines, and excess watermelon side vines should be removed promptly to promote the concentrated supply of nutrients to watermelon growth; the main vine should be promptly directed toward the center of the greenhouse to raise the temperature at the fruiting position; the retained side vines should be promptly arranged so that the watermelon vines and leaves are evenly distributed over the bed surface, improving light energy utilization.

    3. Timely fruit thinning.

    4. Artificial supplementary pollination.According to the flowering habits of watermelon in the greenhouse, pollination should be carried out at 8-9 a.m. On cloudy days, male flowers shed pollen later, so this can be appropriately delayed. Method for preventing male watermelon flowers from shedding pollen late on cloudy and rainy days: pick the male watermelon flowers that will open the next day in the afternoon of the previous day, place them in a dry and warm room, so that the male flowers can open and shed pollen on time the next morning, then use these flowers to pollinate the female watermelon flowers. Artificial pollination should begin with the second female flower of the watermelon, so as to retain the fruit.

    5. Integrated pest and disease control.Plant improved disease-resistant watermelon varieties and practice crop rotation to reduce the occurrence of diseases. Grafting to replace the root system can promote well-developed roots in watermelon seedlings and enhance the watermelon's tolerance to low temperatures and resistance to fusarium wilt. For pest and disease control, it is best to choose aphid-killing smoke agents, chlorothalonil compound smoke agents, thiophanate-methyl, etc., which help control the temperature inside the watermelon greenhouse and reduce pollution.