How to build an orchid greenhouse? Adapting to local conditions is key
Orchid greenhouse construction: because climate conditions differ across regions of China, the methods for building orchid greenhouses also differ. China's climate zones can be divided into fourteen blocks, and if each block is further subdivided according to terrain, altitude and distance from the sea, it can be divided into even more climate sub-blocks. The macro-environmental factors of each block include day and night temperatures, relative humidity, sunshine amount, sunshine hours, wind speed and wind direction, rainfall timing and rainfall amount, snow accumulation dates and snow accumulation amount, etc. Different climate zones have their own special climate conditions.
The mainstream market for Chinese orchids can be divided into four major markets: South China, East China, North China, and the Great Northwest and Northeast markets. The South China market includes Guangdong, Guangxi, Yunnan and Fujian, and its main New Year flowers include varieties such as ‘V31’, ‘Firebird’ and ‘Big Chili’. The East China market includes four provinces and one municipality, namely Jiangsu, Jiangxi, Zhejiang, Anhui and Shanghai, and the commonly used New Year flower varieties are ‘V31’ and ‘Firebird’. The North China market includes Beijing, Shandong, Hebei, Shanxi and Tianjin, and the popular New Year flower varieties are the dark red ‘Jubao’, the ‘04 series’, ‘Firebird’, ‘Red Dragon’, ‘Double Dragon’, ‘V31’, etc. The Great Northwest and Northeast regions are vast in area, and the market has just emerged; their strain demand is also for large red flowers, but they require cold tolerance and resistance to low night temperatures.
The physiological characteristics of these large red flower varieties are not entirely the same. ‘V31’ is characterized by tolerance to low night temperatures; ‘Chaoqun Firebird’ requires high temperature and low light during cultivation; ‘Jubao Red Rose’ is suitable for flower forcing under low night temperatures; and the ‘Red Dragon’ variety produces especially excellent flower quality under long-light conditions.
From the above background of orchid cultivation needs, one can understand the particularity of orchid greenhouses, namely matching them to the climate characteristics of the cultivation region and the physiological characteristics of the varieties. The extreme climates of each region differ, and the structural characteristics of the greenhouses also differ. In South China, greenhouses must resist typhoons, so the lateral pressure bearing capacity of wind-pressure-resistant greenhouses is a key reinforcement point. In North China, the Northeast and the Great Northwest, the bearing capacity for vertical snow pressure is the structural focus. Greenhouse environmental control equipment must also have different functional requirements according to regional characteristics. In South China, short sunshine hours and high relative humidity are the biggest problems, so the greenhouse ventilation rate must be increased. For greenhouses in Central China, stuffy summer heat is the greatest test, so the use of water walls requires increased relative humidity settings to reduce disease transmission.
The main challenge in North China, the Northeast and the Great Northwest is heating equipment for the severe winter cold. When outdoor temperatures in winter are low and the greenhouse needs forced ventilation, measures to protect the plants must be in place. The problem of roof pollution caused by sandstorms in North China also needs a solution.
Therefore, China's orchid industry and greenhouse industry should strengthen exchanges. Orchid growers need to understand greenhouse structures and environmental control equipment, and also understand the basic theory of environmental control; greenhouse operators need to understand the physiological environment required for orchid cultivation. Thus, before building an orchid greenhouse, orchid growers and greenhouse operators should have a common knowledge base and be able to discuss with each other the required greenhouse specifications, so as to build facilities suited to the regional climate characteristics and variety physiological characteristics, and install appropriate environmental control equipment.