Environmental Control of Lily cultivation greenhouse

Lily cultivation, in addition to high-quality bulbs, but also requires strict control in the whole process of lily growth according to the requirements of different varieties on the growth environment, in order to produce lily products with better plant type and higher quality. If the conditions are not well controlled, it will not only affect the plant type of lily, but also affect the plant growth, and even can not blossom normally. The following is a brief introduction to the environmental control in the process of lily cultivation in greenhouse according to the requirements of lily planting.

Greenhouse selection: a good growth environment can ensure the normal growth of lilies. Dutch lily cultivation generally has a suitable greenhouse, and has a variety of facilities to keep the greenhouse in suitable climatic conditions (light, temperature, ventilation, air circulation). In domestic lily cultivation, due to the different climatic conditions and cultivation level, the greenhouse also has diversity, such as greenhouse or multi-span greenhouse, many places can also be planted directly in the open air when the climate is suitable. All localities should choose flexibly according to climatic and economic conditions, but if they need cooling or shading in summer and cooling or lighting in winter, they should be cautious and at least be equipped with basic heating or cooling facilities and suitable irrigation facilities.

Temperature: in order to obtain high-quality products, it is very important to cultivate good roots. In the first three growth cycles or at least before the stem root grows, the optimum temperature is 12 ℃ ~ 13 ℃, which is beneficial to the root growth of lily stem. Too low temperature will prolong the growth cycle, while the temperature higher than 15 ℃ will lead to poor rooting and decline in product quality. After that, the temperature gradually increased, and the suitable temperature for the growth of different strains of lilies was also different, as shown in the attached table.

High temperature and drought will lead to shorter stem and fewer flower bracts; high temperature and humidity will lead to thin and soft stem and thinner leaves; low temperature will slow plant growth and grow longer; sharp changes in temperature and humidity will produce stiff bud and increase the ratio of split bud and scorched leaf, so the whole process of lily is required to maintain appropriate temperature and humidity, and the change is moderate. Ventilation can reduce the temperature and humidity under the condition of high temperature and humidity, make the plant grow healthily and reduce diseases and insect pests. Heating systems are usually used to control the temperature of greenhouses or greenhouses in winter or cold areas. There are many heating methods, which can be oil (coal) hot fan heating, hot water pipe heating, steam pipe heating and so on. The power of the heating system is about 220 watts per cubic meter per hour, which should be selected according to the specific situation.

The use of hot water pipe heating, the heat distribution is more uniform, the operation safety is good, but the pipeline heating is often slow. It is convenient to use oil-fired hot blast stove for heating, but the heat distribution of the system must be ensured to be uniform. In addition, there should be a suitable outlet so that the burning gas can be discharged freely. If burning gases accumulate in the greenhouse, both ethylene and nitric oxide can cause lilies to sprout or grow poorly. Heating systems such as pipes or hoses (up to 40 ℃) can also be installed under the floor.

Ventilation and relative humidity the suitable relative humidity for lily growth is 80%-85%. The relative humidity should not fluctuate too much, and the change should be carried out slowly, otherwise it will cause stress and scorch the leaves of sensitive cultivars. Temperature and relative humidity can be controlled by ventilation, ventilation, shading, watering, heating and other measures, and they often change at the same time in mild, light, windless and humid climates. the relative humidity is usually very high. ventilation must be strengthened to reduce relative humidity. Winter ventilation is best carried out in the morning when the outdoor relative humidity is high. Full attention must be paid to the importance of summer ventilation. The experiment shows that in the area with little rain, the quality of stem and bud of lily planted in open field in summer is better than that in greenhouse with poor ventilation and excessive shade. But it should be noted that it is best to temporarily cover the rain when it rains, so as to prevent Rain Water from harming the stalks, leaves and buds of lilies. If the summer temperature is very high, you can also be equipped with a wet curtain ventilation system to improve the environment in the greenhouse, but this investment is larger. A special paper wet curtain of 10~15cm thickness is installed on the north wall of the greenhouse, and a high-power exhaust fan is installed on the corresponding greenhouse wall. when in use, the whole greenhouse must be closed, the wet curtain pump must be turned on to make the whole wet curtain full of water, and then turn on the exhaust fan to vent the air in the greenhouse and inhale the air outside. When the hot air passes through the wet curtain, the temperature of the air entering the greenhouse is lower due to the evaporation of water. In order to achieve the purpose of reducing the temperature in the greenhouse. It should be noted that the length of the greenhouse with wet curtain ventilation should be strictly controlled at about 40m, and the cooling effect of wet curtain ventilation in areas with low air humidity is better than that in areas with high air humidity. Micro-fog system can also be used to cool down, but the cooling effect is often not satisfactory because of the high humidity. Therefore, in the areas with high humidity and high temperature, the more feasible way to reduce temperature and humidity can only be to strengthen ventilation and proper shading, which can reduce the temperature and humidity of the leaf surface and make the plant grow healthily. In order to ensure smooth ventilation around the greenhouse, the height of the skirt should be raised as much as possible to strengthen ventilation.

Lighting: Asian lilies are very sensitive to lack of light, but there are great differences among varieties. Musk lily is less sensitive than Asian lily, and oriental lily is the least sensitive. Light directly affects the growth, development and flowering of lilies. When the light is insufficient, the plant will grow poorly due to the lack of enough organic matter, the stem is thin and soft leaf is thin, the stem and leaf is curved to light, the bud is thin and the color is light, and in serious cases, it will lead to the shortening of bud drop and vase life. When the light is too strong, it can also inhibit plant photosynthesis. Light also increases the temperature of the medium, which accelerates plant growth and stem elongation. Light regulation can be carried out by shading in summer and adding light in winter. Planting lilies in East China usually does not require light. When growing lilies in winter in the north, consider using a 400W solar lamp with a special reflector per 10m2 to add light when the light is insufficient. And it is best to choose varieties that are not very sensitive to light, and the seeds should be sparse.

It should be shaded when the temperature is too high and the light is too strong in summer, so as to avoid the harm to plant growth caused by high temperature and strong light. Shading directly affects the temperature, humidity and light conditions in the greenhouse. In months with high light intensity, the temperature in the greenhouse may rise rapidly. In this case, proper shading is necessary. Especially in the first three weeks of planting the ball, it is necessary to cover up more light. However, we should pay attention to prevent excessive shading, because excessive shading will lead to lack of light. Shading net can be used for shading, and the method of brushing white ash on the film is also used abroad, but it is not commonly used in China.

Carbon dioxide gas: the content of carbon dioxide in the air is generally about 300ppm, if the concentration of carbon dioxide in the greenhouse can be increased to about 1000ppm, it can significantly promote the growth of lilies, plants become stronger, greener, and the probability of sprouting is less.