Orchids must be in the fresh air in order to properly carry out respiration and photosynthesis, promote metabolism, increase the absorption and running of water and nutrients, and the accumulation of nutrients, reduce pests and diseases, and make orchid plants thrive. So do a good job of ventilation, in order to ensure fresh air, good orchids. First, the infection of orchids is mostly caused by excessively low ambient temperature and humidity, sweltering and no ventilation, and the rapid spread of pathogens and insect pests, especially aphids, whiteflies, scale insects, brown spot and white peitch disease. Second, the ventilation of the venue and shade. The venue should be as spacious as possible, and at a high place, the flower stand can be made of bricks and stones, or the empty flower pots can be placed in the sky upwards, and the orchid pots can be placed to make the orchids 20 to 40 cm from the ground, especially for ventilation. In poor places, the blue pots should be placed as high as possible. Bamboo draperies and bamboo fences are used in the arbors, which are inexpensive and have good ventilation. Third, indoor ventilation is not good, it will make the proportion of various gases in the air to change the relationship, increase harmful gases, reduce useful gases, affect the growth and development of orchids, easy to be infected with mold, rot disease, and even be poisoned . Houses, enclosed plastic sheds or glass sheds, especially those heated with coal, should open windows or uncover the film every day when the room temperature exceeds 10°C. In winter, when the temperature is high at noon, indoors should be closed on all sides. Directional exhaust with fans. The greenhouse temperature is generally high and low, so the air inlet should be in the lower part, and the outlet is in the upper part, the ventilation speed is fast, and the removal of harmful gases is more thorough. Pay attention to the ventilation and spray water at the same time, handle the relationship between ventilation, heat preservation and moisturizing, and prevent cold air from blowing. The density of orchids placed in the interior should not be dense and should be kept close enough. If the area is narrow, the flower bed can be made into a ladder shape. Care should be taken to rinse the surface of the basin with water and spray the front and back of the blue leaf to ensure that the pores are clear. IV. Ventilation of pots and pots Pots with pots, tall feet, thin walls, and highly air-permeable pots should be used, and potted walls and porous pots at the bottom of the pots can also be used. 2. The layering method should be adopted for planting materials or basin soil. If basin soil is used, two or three blocks of small bricks can be used to cover the bottom of the basin, 3 cm thick piece of charcoal should be laid, and then put into the decomposed humus soil. Mix the sand with the river, to the 1/2 height of the pot, add a layer of 3 cm thick burned slag, and then cover with mixed soil to the edge of the pot, so that the orchid has a gas circulation environment. 3. The number of plants planted in each pot should not be too much. If there are many plants and dense foliage, planting should be carried out in a timely manner. The weeds, diseased leaves and dead leaves in the blue pots should be regularly removed to facilitate ventilation.