Detailed Explanation of Key Greenhouse Cucumber Cultivation and Management Techniques
?1. Do a good job of heat preservation, warming, and cold protection both inside and outside the greenhouse.
The most suitable temperature for young cucumber fruit development is 25-30°C during the day and 13-16°C at night. The minimum greenhouse temperature must not be lower than 8°C, otherwise it will cause cold damage, resulting in a large number of flower and fruit drop, or even wilting of the cucumber vines. Therefore, before a cold wave arrives, add double-layer plastic film around the plastic greenhouse as much as possible, and add double-layer straw curtains between the two layers of film on the west and north sides to prevent cold air from attacking. At the same time, spread a layer of fresh, dry rice or wheat straw in the large planting rows to increase soil temperature. In addition, on rainy and snowy days, a layer of agricultural film or rainproof cloth matching the size of the greenhouse roof must be covered over the straw curtains to prevent rain and snow from soaking the straw curtains and reducing the insulation effect. If conditions permit, at night, add 2-3 more layers of shade netting between the two films whenever possible; this will provide even better cold protection and insulation.
????2. Enhance and regulate lighting.
On sunny days, while ensuring that the greenhouse temperature will not drop too much, uncover the straw curtains and shade netting early and cover them late, so that the plants can receive as much light as possible. To improve the light transmittance of the greenhouse film, clean the greenhouse film once a week. During rainy and snowy weather, also pull open the straw curtains during the noon pause in rain and snow, so that the plants can receive light for a short time. Never leave the straw curtains unopened for several days. When continuous long-term rainy weather suddenly turns sunny, the straw curtains should be opened gradually at intervals so that the plants adapt to light gradually. Never uncover the curtains all at once after long-term rainy and snowy weather and expose the plants to strong full light. At the same time, in autumn and winter, create conditions as much as possible to hang reflective curtains, etc., which can also significantly improve and increase the lighting conditions inside the greenhouse.
?3. Strengthen fertilizer and water management.
Generally, depending on the soil moisture condition inside the greenhouse, irrigate once every ten days to half a month, around 10 a.m., and try to adjust the water temperature and soil temperature so that the difference between them is 2-3°C. When irrigating, never flood-irrigate and run water freely regardless of weather, timing, soil moisture, or seedling size. It is better to use methods such as furrow irrigation under film, hole irrigation, and drip irrigation. When base fertilizer is sufficient, additional fertilization may not be needed in late autumn and winter. When supplementary fertilizer is truly needed according to growth conditions, apply 15-25 kg of urea and about 10 kg of potassium sulfate per mu along with irrigation. Every 15-20 days, combined with pesticide spraying, foliar fertilizer can be sprayed, such as photosynthetic micro-fertilizer or a mixed solution of 0.2% potassium dihydrogen phosphate and urea.