Key points of raising seedlings of celery

Key points of celery seedling raising techniques celery can be cultivated all the year round, and the time and methods of raising seedlings vary with the time and methods of cultivation. 1. Cultivation and seedling raising in spring (1) seed treatment. 5-6 days before sowing and 1-2 days before sowing. When drying seeds, you can't spread them evenly on the cement floor. When soaking seeds for 24 hours, it is necessary to change the water for 1 or 2 times. (2) sowing seeds. The time of sowing seedlings in open field is from late October to the end of November, covering and anti-freezing in overwintering period, or raising seedlings in greenhouse in the first and middle of February. The sowing rate is 10 grams per square meter of seedbed and the seed consumption is 7500 grams per hectare. When sowing, each kilogram of seeds can be mixed with 5kg of fine soil before sowing. Sowing back cover 0.3 cm fine soil layer and sunshade net. (3) seedbed management. Keep the humidity of the seedling bed before sowing and remove the sunshade net when the seedling top soil. After emergence, the seedling bed should maintain a certain humidity, but it should not be watered more. The seedlings began to grow 2-3 days after emergence, and the seedlings began to grow again in the 2-leaf stage. When the seedlings grow to 3-4 leaves, properly control watering to refine the seedlings to promote the development of roots. When the temperature drops below O ℃, it can be covered with sunshade net or grass curtain. If the seedlings are raised and cultivated in the greenhouse, more fertilizer can be applied in the later stage of seedling cultivation to promote their growth. If the night temperature in the greenhouse is too low, you should pay attention to heat preservation. 2. The sowing period of summer cultivation is from late March to late May. The sowing rate is 7 grams per square meter of seedbed. The seeds were soaked for 24 hours and then sowed. The soil cover is 0.8cm. After emergence and time seedlings, the distance between seedlings is about 2 cm. If sown in late April, the film will no longer be covered. Sunshade nets should be built before sowing seedlings for moisturizing. The specifications and requirements of nursery bed are the same as those of spring cultivation. 3. In autumn, the sowing period is from the first ten days of June to the middle of July, and from the end of July to the end of August. Because the planting and sowing date in autumn is in the summer high temperature season, and the suitable temperature for celery germination is 15-25 ℃, it is difficult for celery to emerge beyond 30 ℃, so seed treatment must be carried out. (1) variable temperature treatment. Wash the soaked seeds, wrap them with gauze, squeeze out some moisture, put them in the refrigerator, keep them for about 5 ℃ for 2 days, and rinse with clean water twice a day in the morning and evening. Then hang the seeds in a bright 15: 22 ℃ environment, still wash the seeds with cold water twice a day, and then blow them with an electric fan for 5 minutes to remove excess water from the seeds and prevent excessive moisture from causing insufficient oxygen and affecting germination. Generally, it can sprout after 4-5 days of treatment. (2) hormone treatment. After soaking the seeds with 5 mg / L gibberellin (920) for 12 hours, rinse the seeds with clean water, then soak the seeds with clean water for 8 hours, and then spread them out in the light environment of 15: 22 ℃ according to the above method. (3) cold treatment. Squeeze the seeds that have been soaked according to the first method in gauze, then hang them in a deep well 40cm above the surface of the water. Rinse twice a day, the same method as above. It can sprout after 5-6 days. After sowing, cover a layer of 0.8 cm thick fine soil, cover 1-2 layers of sunshade net, and then spray enough water to keep the soil moist. Remove the sunshade net covering the ground in time after emergence. The seedlings were planted once at the time of true leaves, once again at the age of 2 leaves, the distance between seedlings was 4 cm × 2 cm, and planted at the time of 4-6 leaves. 4. Sowing seedlings in winter from late August to early September can be carried out in the greenhouse, and it still needs to be covered with sunshade net in case of high temperature. As most of the seeds used for cultivation in winter are new seeds harvested in the same year, sowing fashion is in the dormant period, and the method of breaking dormancy is the same as that in autumn. The sowing method can refer to autumn cultivation and seedling raising. In nursery bed management, if the temperature has dropped, it can be carried out according to the method of raising seedlings in spring.