In lilies, the choice of cover technologies needs to be closely linked to regional climatic characteristics. The high summer temperatures in the south further increase the temperature of the ground and interfere with the normal growth of the lilies, so that they are not recommended for use; the relatively low temperatures in the north, such as hebei, shandong and north-east, can be covered by black membranes, while acting as a disincentive to weeds。
In cold and dry weather areas such as the central province of gansu, liviculture experiments have shown that surface grass and membrane cover can effectively increase soil temperature and water content. The average annual surface soil temperature is 15. 72 °c for membrane cover, 14. 62 °c for grass and only 12. 30 °c for open ground; 21. 21 % of the average annual soil water content is covered by membrane cover, 18. 86 % of ground cover and 16. 63 % for open ground. In both ways, lilies can be promoted, and the membranes are more effective in improving the water heat conditions of the soil, but surface grass can achieve resourceization and lower ecological costs of agricultural waste. For the lanzhou lily, autumn membrane cultivation increased by 21. 2 per cent compared to traditional unrepeated membrane production and 4. 5 per cent over the top of the membrane production, which directly affected production performance during the coverage period。
The northern part of the country needs to strengthen its temperature protection measures for the lilies winter. In beijing, hebei and liaoning, the lowest annual temperatures range from 15°c to 25°c and lilies are prone to freezing. Cold-resistant varieties such as lanzhou lily and asia lily should be selected for planting, with the use of seedlings to prevent water accumulation; in winter, the plant should die. After yellow, cover the ground with corn straws, straws, etc. (not less than 15 cm thick) and increase the temperature protection by adding a twig or black membrane. The north side of the plot can be constructed to reduce the impact of the cold, while digging drains to prevent the melting of snow and the infiltration of water into the root。
In the south, such as hunan and jiangxi, the climate is very wet and rainy and suitable for planting lily between september and october in the autumn, with a distance of 30 cm and a distance of 15 to 20 cm. The introduction of membrane cover during winter can increase early spring temperatures and promote seedlings, but early digging of drains is required to avoid rain and snow that can lead to the rotting of stalks. High-altitude areas such as yunnan and sichuan, which are characterized by high temperatures and sufficient light, are suitable for selecting cold-resistant varieties, enhancing the application of organic fertilization to increase soil fertility and increasing yields in combination with rational dense planting。
There are significant differences in the management of the coverage of different varieties: the asian lilies are more cold-resistant and the northern field needs greater coverage over the winter season; the eastern lilies are less cold-resistant and are more suitable for southern or greenhouse cultivation; and the range of dry areas suitable for the cold in lanzhou has had a significant effect on the production of the autumn membranes. In winter management, dry leaves need to be cleaned in time for the soil to be frozen, with pine fields to be plowed and consumable organic fertilizers to supplement nutrients; cold areas in the north can be buried deep or conserved in greenhouses, while the south needs to focus on soil moisture control to avoid a moist cold environment causing rods to change。
At the core of the liviculture cover technology is the adaptation of the region's climate and variety characteristics and the choice of the right approach, combined with factors such as temperature conservation, conservation and eco-efficiency, to effectively improve yields and quality。
