High-yield cultivation techniques for cucumbers in large arch greenhouses for late-autumn production

The external environment for late-autumn greenhouse cultivation is a hot, rainy season in the early stage and a sharp drop in temperature in the later stage. Based on many years of experience, in Heze City, Shandong Province, direct sowing under the covered greenhouse is generally done in early August, and the cucumbers are supplied to the market from late September to December, connecting with the supply from autumn-winter crops in solar greenhouses. The yield per mu is about 4,500 kg, and the profit is about 7,000 yuan, with notable social and economic benefits.
Variety selection. Generally, varieties with strong disease resistance, tolerance to high temperatures in the early stage and low temperatures in the later stage, and dense fruit set should be selected, such as Jinyan No. 4, Jinchun No. 4, Jinchun No. 5, Jinyou No. 11, etc.
Sowing The sowing period is generally early August. The sowing method is usually direct sowing under the covered greenhouse; after sowing, open the surroundings for ventilation, leaving only the film at the top for shade and rain protection. Open furrows on the ridge surface according to the row spacing, 3 cm deep, water thoroughly, and sow the pre-germinated seeds at a plant spacing of 25 cm, with 2 to 3 seeds per hole. After sowing, cover with 1.5 cm of soil. Seedlings generally emerge after 3 days, and thinning is done after 2 true leaves appear.
Temperature management In the early stage, the outside weather is still hot with strong light, which is not suitable for the normal growth and development of cucumbers. At this time, in addition to covering the top of the greenhouse with film, open the surroundings widely for ventilation to cool the shed and prevent rain. When it rains, the film can be lowered, and it should be opened immediately after the rain. If conditions permit, it is best to cover the greenhouse with shade netting, removing it in the morning and evening and on cloudy and rainy days, and covering it at noon during high temperatures and strong sun. When the cucumbers enter the full fruiting period from mid-to-late September to early October, the natural temperature is more suitable for normal cucumber growth, so remove the shade netting. During the day, keep the temperature inside the greenhouse at 25°C to 30°C, and at night at 15°C to 18°C. When the outside temperature is above 15°C, open the ventilation openings. After mid-October, the outside temperature gradually decreases, so the ventilation amount should be gradually reduced, maintaining 25°C to 30°C during the day and 13°C to 15°C at night. When the temperature inside the greenhouse drops below 10°C, lower the trellis for management, add a small arch greenhouse inside, and extend the fruiting period. When the nighttime temperature drops to 5°C, the cucumbers stop growing and all vines can be pulled up.
Plant adjustment In the early stage, pay attention to trellising and tying the vines, remove the lower side branches, and remove male flowers and tendrils; in the later stage, use side branches to bear fruit to increase yield. When the plant height approaches the greenhouse top, topping can be done to promote the sprouting of side branches. When there are few female flowers on the main vine, after female flowers appear on the side branches, leave 2 leaves and pinch the tips to cultivate return cucumbers. In addition, pay attention to the prevention and control of pests and diseases.