The ancient county of Huize, located in the northeast of Yunnan, China, has an altitude of 2120 m, an average annual temperature of 12.7 °C, strong sunshine, and a large temperature difference between day and night, which is very suitable for the production of leafy vegetables. Here, there is a hydroponic leaf vegetable base, which adopts advanced soilless cultivation and integrated water and fertilizer planting techniques to produce high-quality, pollution-free leaf vegetables. This is the hydroponic leaf vegetable base of Yunnan Weikang Modern Agricultural Vegetable Base.
The Base covers an area of nearly 100 hectares. It is jointly constructed and operated by Yunnan Weikang Agricultural Company and Hong Kong Yacuibao Vegetable Group. The total project investment is 110 million RMB. The film greenhouse of this hydroponic leafy vegetable base has a span of 8 m, a bay of 4 m, a column height of 4 m, and a total height of 6 m (including external shading system). The greenhouse frame is made of hot-dip galvanized steel with a zigzag steel surface, which will not rust in a high humidity environment for 20 years.
Using natural spring water for planting, seeds, and nutritional formulas from the Netherlands, together with planting technology from Australia, has helped Yacuibao to become an influential leafy vegetable production and sales enterprise in China.
The project started construction in July 2019. It was completed and put into production in May 2020. It mainly produces coral lettuce, butter lettuce, Boston lettuce, red oak leaf lettuce, romaine lettuce, watercress, and other salad vegetables. The high-end salad vegetables exceed 1500 tons, and the hydroponic leaf vegetables produced are all supplied to the high-end consumer markets in Hong Kong, Shenzhen, Guangzhou, and Shanghai, and are very popular among consumers.
The energy-saving greenhouse, developed in Southern China, is economical and practical. According to the climatic characteristics of the large temperature difference between day and night in Huize, Huawang Company focused on improving the thermal insulation performance of the greenhouse, keeping the heat of the day as long as possible inside the greenhouse, so that when the outside temperature is -2~3 °C, the greenhouse can still maintain the temperature at which the vegetables are suitable to grow. In this case, the energy consumption of the greenhouse can be minimized, and the investment can be minimal. Huize County has a high altitude and strong light, so the greenhouse is equipped with an external sunshade system from Bluky and uses Japanese scattering film as a greenhouse covering film, which can diffuse sunlight, optimize photosynthesis, and effectively relieve the burns of leafy vegetables with high-intensity light.
In addition to changes in the structure of the greenhouse according to the local climate, there are also many "tricks" in the production process of leafy vegetables. The pipes used for hydroponic leafy vegetables are specially made by Hong Kong Yacuibao Vegetable Group. They have black and white two layers, which can better control the water temperature, and also have the function of inhibiting the growth of moss and the occurrence of diseases. The greenhouse is also equipped with Ridder's integrated water and fertilizer system from the Netherlands, which can accurately adjust the water and fertilizer strategy in real-time according to the growth status of the crop, achieve high yield and fully automated production of vegetables, and greatly reduce the labor input.
"Today's vegetable production, facilities, mechanization, and automation are the major trends, but it is still necessary to pay attention to the practicality of the greenhouse while developing technologies so that the greenhouse can better produce high yields. And provide a guarantee for high-quality vegetable production," said Tu Guoyuan, general manager of Guangdong Huawang Agricultural Facilities Technology Co., Ltd. "While continuing to deepen the greenhouse construction technology, the company will focus on researching ways to grow different vegetables in different regions, so that the greenhouse can be better integrated with vegetable production."