What indoor temperature is suitable for growing orchids in northern China

The growing environment of Chinese orchids is similar to what most plants require: water, sunlight, nutrients, temperature, humidity and so on. But among these conditions, if Chinese orchids are to grow normally, the conditions they need have their own particularities. For example, the requirement for air humidity is an important one among many conditions. Generally speaking, the temperature required for Chinese orchid growth is between 18°C and 28°C; the humidity is above 80%. In the Yangtze River basin and areas to the south, because the climate is warm, rainfall is abundant and the air is humid, the humidity requirement of Chinese orchids is hardly affected at all. But in the northern regions north of the Yellow River basin, because the air pressure is relatively high, the climate is dry and the air humidity is relatively low, especially during the annual winter heating period and in spring, the indoor temperature is around 20°C while the air humidity is only around 40%, which cannot meet the needs of Chinese orchid growth. So how to increase air humidity is the key for northern orchid growers to grow Chinese orchids well indoors. For this reason, many orchid growers try every means to increase air humidity, such as adding water trays and using humidifiers. In my own experience, rather than increasing the humidity of the air externally, it is better to adopt the wet methodorchid growingand improve it. First, the orchid pot and growing medium. For the orchid pot, choose a cylindrical clay pot or a purple clay pot with many holes in the walls, for good ventilation. For the growing medium, choose a granular medium, which can be a mixed medium of 10% charcoal (acid-treated), 40% volcanic rock and 50% Xiantu. After all, which mixed medium to choose depends on the orchid grower's own experience, but it must be a granular medium. The lower 1/3 of the orchid pot is foam blocks; the middle 1/3 is a granular mixed medium with a diameter of more than 10cm; the upper 1/3 of the pot is granules with a diameter of less than 1cm. The reason for using a granular medium is to suit the wet methodorchid growing, so that the humidity is high without damaging the roots due to excess water. Before potting, the growing medium must be fully soaked in water and disinfected. When potting, keep the orchid roots in full contact with the growing medium. Second, treatment of the pot surface. Southern orchid growers mostly place sphagnum moss on the pot surface to increase humidity. But indoor humidity in the north is low, and after laying it down it is not easy to judge whether the potting soil is dry or wet, and plants on the pot surface are not easy to keep alive, so this method is not suitable. Generally, the height of the growing medium should be atorchid plant's axil 1/2 point, but when using a granular mixed medium, because its granules are larger and its ventilation is good, the height of the mixed medium can be about 1cm above the pseudobulb. Using the wet method to plant orchids can maintain humidity. Third, the watering method. Generally, water once every 3-4 days. If there is snow or rain, the air humidity is relatively high, so it can be decided according to the specific weather conditions. Spray water on the leaves once each in the morning and afternoon every day (be careful not to spray intoorchid plant's center, to prevent rot of the shoots). The medium on the pot surface should also be sprayed with water to keep it moist. It should be noted that the wet methodorchid growingrequires controlling the number of waterings; once water is cut off for a long time and the Xiantu in the growing medium dries out completely, it is very difficult to make it contain sufficient water again. I have used the above method for a long time, and the effect is good; the indoor humidity can be maintained at around 80%. Orchid growers can adapt it according to their own actual conditions.