Multi-layer mulching to improve Thermal Insulation performance key points of asparagus mulching cultivation in greenhouse

The cultivation of asparagus in winter and spring by using multi-layer mulching methods such as greenhouse, inner greenhouse, small arch shed and plastic film can significantly improve the cold protection and heat preservation ability of the greenhouse and realize the high yield of asparagus in winter and spring.

Asparagus multi-layer mulch

Main points of cultivation: (1) selection of varieties. The price of asparagus in winter and spring in greenhouse before March is 3 times higher than that in later stage, which shows the importance of early maturity of varieties. At the same time, the characteristics of strong disease resistance, sturdy stem, high yield and high quality should be taken into account. Combined with years of practice, it is suitable to grow early in California. Before mulching, remove withered stems and leaves, weeds in the field, ploughing and loosening the soil, applying basic fertilizer in the ditch, combined with soil moisture, watering properly, in order to improve the fertilizer utilization rate.

(2) temperature and humidity control. Uncover the small arch shed film and non-woven fabric in time according to the weather conditions. The temperature of the greenhouse is controlled at 20: 30 ℃ during the day and 15 ℃ at night. If the weather is cold or rainy or snowy, the film will be released in the morning and covered early in the afternoon. When the greenhouse temperature exceeds 20 ℃, uncover the plastic film and non-woven fabric of the small arch greenhouse and carry out the management of bamboo shoots, bamboo shoots and so on. When the greenhouse temperature exceeds 30 ℃, properly uncover the greenhouse film on the leeward side of the greenhouse, ventilate and keep warm around 4: 00 p. M. Multi-layer mulching has high moisture retention, so it should be properly ventilated at noon to reduce the small arch shed and soil moisture and prevent the occurrence of diseases.

(3) Water and fertilizer management. According to soil moisture, drip irrigation under plastic film, not furrow irrigation, reduce the humidity of the greenhouse as much as possible. Before multi-layer mulching, budding fertilizer was applied from late December to early January, with 1000 kg of organic fertilizer, 300kg of ternary compound fertilizer, 15kg of superphosphate and an appropriate amount of micro-fertilizer per mu. When the temperature rises from late February to early March, asparagus scale bud germination and tender stem growth speed up, a large number of new roots are formed, and enough nutrients are needed. 1000 kg of organic fertilizer and 20 kg of urea can be applied per mu.

(4) Prevention and control of diseases and pests. The main diseases of asparagus are stem blight and root rot. Azoxystrobin, isobarbazide, carbendazim and other drugs are used to irrigate or spray the stem blight. 40% biguanidine trioctylbenzene sulfonate wettable powder and white latex adhesive are also used to coat the stem. The main pests are nocturnal moths, aphids and thrips, which occur mainly from March to May. Poison baits, yellow boards, insecticidal lamps are mainly used, and trichlorfon, cypermethrin and phoxim are sprayed to control them.

(5) Management of bamboo shoots. Asparagus cultivated in multi-layer mulching greenhouse in winter and spring, early-maturing varieties, can produce bamboo shoots within a week, should pay attention to check, punctured the plastic film in time, let the tender bamboo shoots grow smoothly and prevent the tip of bamboo shoots from bending.

(6) leave the mother stem in spring. Keeping spring mother stem is very important. From late March to early April, 3-4 strong mother stems with uniform distribution, no diseases and insect pests and thick 1cm were selected for each plant, and all of them were harvested, and the number of retained mother stems increased according to the growth years and cultivation density of asparagus. At the end of bamboo shoot picking, enough fertilizer was applied for plant growth.