Detailed Explanation of Key Points of Greenhouse Watermelon Cultivation Techniques

Whenever summer comes, watermelon becomes the best-selling fruit, and almost every household eats it every day. Watermelon is rich in nutritional value and tastes good, making it the most popular fruit in summer. Watermelon sales in summer are particularly large and often fall short of demand, so greenhouse watermelon cultivation techniques have emerged to increase watermelon yield.

Greenhouse Watermelon Cultivation Techniques

1. Variety selection: Choose varieties with early maturity, high quality and strong disease resistance, such as Jingxin, Hongshuangxi, Qinguan Xianfeng, Lidu, etc.

2. Cultivation method: For watermelons marketed from mid-May to early June, use three-film mulching cultivation (plastic film, small arch shed, outer shed film); for watermelons marketed in June, use two-film mulching cultivation (plastic film, outer shed film).

3. Seedling selection standards: 3-4 true leaves, thick and strong stems, and thick leaves.

4. Preparation before planting

Finely prepare the soil and apply sufficient base fertilizer. Apply 3000-4000 kg of decomposed organic fertilizer, 100 kg of decomposed cake fertilizer, 40-50 kg of superphosphate, and 15-20 kg of potassium sulfate per mu, then deeply plow, level and form ridges.

Cover the shed in advance, and lay drip irrigation tape and plastic film. 15-20 days before planting, fully cover the ridge surface with plastic film, which can raise the ground temperature and reduce soil moisture evaporation. Then set up the arch film, do a good job of deeply burying and fixing the ground anchors of the film-pressing line, and fix the shed film with the film-pressing line to prevent strong winds from damaging the shed film. Before covering with plastic film, lay the drip irrigation tape. The width of the drip irrigation tape is preferably 3-4 cm, and one or two tapes are laid per ridge. The drip irrigation tape should be about 10-15 cm away from the planting row.

5. Plant at the right time. For three-film mulching cultivation, plant from late February to early March; for two-film mulching cultivation, plant from mid-to-late March. In principle, planting can only be done when the 10 cm ground temperature is stable at or above 13 degrees C. When planting, choose a sunny morning, follow a plant spacing of 45-50 cm, punch holes, plant seedlings and cover with soil, keep the cotyledons consistent with the planting direction, water thoroughly after planting, seal the planting holes, and cover with a small arch film.

Cultivation density: Ground-creeping cultivation: row spacing 1.5 m, plant spacing 0.5 m, about 800-900 plants per mu; trellis cultivation: row spacing 1.0 m, plant spacing 0.5 m, about 1300-1400 plants per mu.

Field Management of Greenhouse Watermelon Cultivation

1. Pruning and vine pressing

Use the three-vine pruning method for pruning, and use the open pressing method for vine pressing.

2. Artificial pollination

Perform artificial pollination on the morning of the day the female flowers open, before 9 o'clock. Pick pollen from male flowers that open on the same day and smear it on the stigma of the female flowers.

3. Selecting and retaining fruit buds

Follow the six rules of not retaining fruit when setting watermelons: do not retain the root fruit; do not retain overly long fruit; do not retain double fruit; do not retain deformed fruit; do not retain diseased or insect-damaged fruit; do not retain bruised fruit.

4. Harvest at the right time

Early-maturing watermelons generally need 30-35 days from fruit setting to fruit maturity. Attention should be paid to calculating their maturity time and harvesting in time, which helps increase yield and ensure fruit quality.

Grafting Techniques for Greenhouse Watermelon Cultivation

1. Grafting time: Grafting can be carried out after the cotyledons of the rootstock seeds have flattened out, which is also the best time for grafting.

2. Grafting method: Use the top insertion method. During grafting, remove the growing point of the rootstock, use a bamboo skewer at the cut of the rootstock to insert obliquely downward at 45 degrees along the direction of the cotyledon line into the hypocotyl below the cotyledons, to a depth of 0.5-1 cm, with the top of the bamboo skewer reaching the cortex on the other side of the hypocotyl below the cotyledons. Then take out the scion seedling, place it on the index finger and cut it off at 45° with a blade. After trimming the scion seedling, immediately pull out the bamboo skewer and insert the scion seedling along the direction of the bamboo skewer hole.

3. Grafting management: Keep the temperature at 25 degrees C, and keep the low temperature at 24 degrees C. For the first three days after grafting, keep it closed without ventilation or air exchange, so that the air humidity reaches saturation. One week before planting, lower the ground temperature to 15-13 degrees C, and lower the air temperature to 23 degrees C during the day and 13 degrees C at night, with the nighttime minimum not lower than 10 degrees C for hardening seedlings, so that the seedlings are close to the environmental temperature after planting.

Watermelon Cultivation Pest and Disease Control Techniques

Common types of pests and diseases. Damping-off at the seedling stage, vine cutting disease at the vine extension stage, vine blight and anthracnose at the fruiting stage, and anthracnose, leaf blight, powdery mildew, viral disease, etc. at the senescence stage. In May, yellow squash beetles, flower thrips, aphids, etc.; in June, flower thrips, aphids, melon borers, etc.; in July and August, noctuid moths, red spiders, etc.; in September and October, noctuid moths, melon borers, yellow thrips, tobacco thrips, etc.

Integrated control. Mix and alternate medications according to the occurrence of watermelon pests and diseases. Avoid spraying on hot, high-temperature days. Choose to spray before 9 a.m. on sunny days, after 4 or 5 p.m., or on cloudy days. Commonly used control agents include: 70% thiophanate-methyl, 75% chlorothalonil, 10% difenoconazole, 50% dimethomorph, 25% pyrimethanil, 72% agricultural streptomycin, 50% carbendazim, 65% zineb, 25% prochloraz, 3% kudujing, etc. for disease control; Leitong (24% methoxyfenozide suspension concentrate), 1%-3% emamectin benzoate emulsifiable concentrate, Anda (150 g/L indoxacarb suspension concentrate), 10% chlorfenapyr suspension concentrate, Caixi (25 g/L spinosad suspension concentrate), 10%-70% imidacloprid, 25% pymetrozine, 2% abamectin, 20% flubendiamide, 5% chlorantraniliprole, 3% acetamiprid, etc. for pest control.

Through the above content, we have learned that greenhouse watermelon cultivation is relatively technically demanding, and if you want to grow it in a greenhouse, you need to master the techniques well. Watermelon is rich in water, contains a large amount of vitamins and is easily absorbed by the human body, and also has beauty and skincare effects! Although eating watermelon has many benefits, it should not be eaten in large quantities, or you may get diarrhea!