Key Points of High-Yield Cultivation Techniques for Spring Chinese Cabbage in Greenhouses
Key Points for High-Yield Cultivation of Spring Chinese Cabbage in Greenhouses
(Agricultural Wealth Network) (1) Variety selection. As a variety for spring Chinese cabbage cultivation, the requirements are relatively strict, and this is the key to success or failure in cultivation. Varieties with a short growing period and strict vernalization requirements should be selected. At present, excellent varieties suitable for spring Chinese cabbage cultivation in China include Beijing Xiaobaikou, Shigatse 1, Luchunbai l, etc. In addition, Japanese varieties such as Wushuang, Chunguang, and Disease-Tolerant 60 Days can also be used.
(2) Sowing at the appropriate time. Chinese cabbage is a seed-vernalization-type crop. Germinating seeds can pass through vernalization after 15 to 30 days at a low temperature below 10 °C, and under long-day conditions with suitable temperatures they very easily bolt and flower. Therefore, sowing must not be too early. For greenhouse cultivation, direct sowing in the greenhouse is generally done in mid-to-late February; if conditions permit, seedlings can also be raised on electric heating beds in mid-to-late January and then transplanted into the greenhouse in late February. Spring Chinese cabbage in greenhouses mainly uses the principle of "de-vernalization" through the high daytime temperatures inside the greenhouse to prevent early bolting, thereby promoting earlier head formation and earlier marketing.
(3) Cultivation points. Apply sufficient base fertilizer before sowing, at least 3500 kg of barnyard manure per mu, plus 15 kg of urea, 30 kg of superphosphate, and 15 kg of potassium chloride. The soil should be leveled and finely prepared, formed into high beds, and sown on a sunny day when soil moisture is good. Practice rational close planting, opening holes at a spacing of 40 cm × 25 cm, sowing 5 to 10 seeds per hole, covering with fine soil after sowing, using 100 - 150 g of seed per mu. Thin seedlings promptly after emergence, and final thinning at the 5 to 6 -leaf stage, leaving 1 plant per hole. If plug tray seedling raising is used, it is most suitable. After planting, do a good job of multiple-layer nighttime covering for cold protection, and especially pay attention to preventing the sustained effects of low temperature, so as to prevent premature bolting caused by passing through low-temperature vernalization. On the basis of sufficient base fertilizer, fertilizer and water should be applied early to promote growth. During the seedling stage and rosette stage, topdressing should be applied several times according to the growth of the Chinese cabbage. After final thinning, apply 10 kg of urea in furrows between rows. At the end of the rosette stage and the beginning of the heading stage, apply 15 - 20 kg of nitrogen-phosphorus-potassium compound fertilizer per mu to promote filling of the leaf heads. Topdressing for spring Chinese cabbage should be timely and early, with sufficient fertilizer and water, "rising in one rush." Only relatively vigorous vegetative growth can achieve higher yields. In addition, to some extent, good growth can also reduce or delay the occurrence of premature bolting.
(4) Pest and disease control. After greenhouse spring Chinese cabbage enters the rosette stage and heading stage, as temperatures gradually rise, various pests and diseases occur frequently, such as downy mildew, white spot disease, and soft rot, as well as cabbage caterpillars, aphids, diamondback moths, etc., which should be controlled early. Also pay attention to ventilation and air exchange, and the greenhouse temperature should preferably not exceed 25 °C. ① Downy mildew and soft rot: refer to the "Winter Lettuce Cultivation" section. ② White spot disease: at the initial stage of disease, spray with 50 % carbendazim 800 to 1000 times solution, or disinfect seeds with a ratio of 0 . 1 kg carbendazim mixed with 50 kg seed. ③ Cabbage caterpillars, aphids, and diamondback moths: refer to the "Chinese Kale Cultivation" section.
(5) Timely harvest. When the leaf heads of Chinese cabbage have 5 - 6 leaves forming a heart, they can be marketed according to market demand. Pick the ones with better head formation and harvest them first, trim them according to commercial vegetable requirements, and market them promptly. Greenhouse spring Chinese cabbage is marketed during the spring slack period from late April to May, with a yield of about 3000 kg per mu.
(2) Sowing at the appropriate time. Chinese cabbage is a seed-vernalization-type crop. Germinating seeds can pass through vernalization after 15 to 30 days at a low temperature below 10 °C, and under long-day conditions with suitable temperatures they very easily bolt and flower. Therefore, sowing must not be too early. For greenhouse cultivation, direct sowing in the greenhouse is generally done in mid-to-late February; if conditions permit, seedlings can also be raised on electric heating beds in mid-to-late January and then transplanted into the greenhouse in late February. Spring Chinese cabbage in greenhouses mainly uses the principle of "de-vernalization" through the high daytime temperatures inside the greenhouse to prevent early bolting, thereby promoting earlier head formation and earlier marketing.
(3) Cultivation points. Apply sufficient base fertilizer before sowing, at least 3500 kg of barnyard manure per mu, plus 15 kg of urea, 30 kg of superphosphate, and 15 kg of potassium chloride. The soil should be leveled and finely prepared, formed into high beds, and sown on a sunny day when soil moisture is good. Practice rational close planting, opening holes at a spacing of 40 cm × 25 cm, sowing 5 to 10 seeds per hole, covering with fine soil after sowing, using 100 - 150 g of seed per mu. Thin seedlings promptly after emergence, and final thinning at the 5 to 6 -leaf stage, leaving 1 plant per hole. If plug tray seedling raising is used, it is most suitable. After planting, do a good job of multiple-layer nighttime covering for cold protection, and especially pay attention to preventing the sustained effects of low temperature, so as to prevent premature bolting caused by passing through low-temperature vernalization. On the basis of sufficient base fertilizer, fertilizer and water should be applied early to promote growth. During the seedling stage and rosette stage, topdressing should be applied several times according to the growth of the Chinese cabbage. After final thinning, apply 10 kg of urea in furrows between rows. At the end of the rosette stage and the beginning of the heading stage, apply 15 - 20 kg of nitrogen-phosphorus-potassium compound fertilizer per mu to promote filling of the leaf heads. Topdressing for spring Chinese cabbage should be timely and early, with sufficient fertilizer and water, "rising in one rush." Only relatively vigorous vegetative growth can achieve higher yields. In addition, to some extent, good growth can also reduce or delay the occurrence of premature bolting.
(4) Pest and disease control. After greenhouse spring Chinese cabbage enters the rosette stage and heading stage, as temperatures gradually rise, various pests and diseases occur frequently, such as downy mildew, white spot disease, and soft rot, as well as cabbage caterpillars, aphids, diamondback moths, etc., which should be controlled early. Also pay attention to ventilation and air exchange, and the greenhouse temperature should preferably not exceed 25 °C. ① Downy mildew and soft rot: refer to the "Winter Lettuce Cultivation" section. ② White spot disease: at the initial stage of disease, spray with 50 % carbendazim 800 to 1000 times solution, or disinfect seeds with a ratio of 0 . 1 kg carbendazim mixed with 50 kg seed. ③ Cabbage caterpillars, aphids, and diamondback moths: refer to the "Chinese Kale Cultivation" section.
(5) Timely harvest. When the leaf heads of Chinese cabbage have 5 - 6 leaves forming a heart, they can be marketed according to market demand. Pick the ones with better head formation and harvest them first, trim them according to commercial vegetable requirements, and market them promptly. Greenhouse spring Chinese cabbage is marketed during the spring slack period from late April to May, with a yield of about 3000 kg per mu.