What should I do if the leaves of Cymbidium turn yellow?
Yellowing of Cymbidium leaves is a common problem during maintenance, which not only affects the ornamental value, but may also indicate a plant health crisis. This article analyzes four core maintenance scenarios and systematically sorts out the causes of yellow leaves and corresponding solutions to help you quickly restore plant vitality. 1. Environmental humidity control plan Air dryness causes yellowing symptoms The original environmental humidity of Cymbidium hybridum is 60%-80% all year round, and leaf margins are prone to scorch during the northern heating season or air-conditioned rooms. It is recommended to apply foliar spray from 8-10 and 15-17 every day, and use water basins or ultrasonic humidifiers to keep the environmental humidity stable. Water spraying techniques are standardized. Use an atomized spray can to spray evenly 30cm away from the leaf surface to avoid water droplets accumulating in the leaf core and causing rot. Focus on spraying the ground within 1 meter around the plants to establish a humidity buffer layer through evaporation. 2. Temperature stress treatment plan Characteristics of low-temperature damage When the ambient temperature continues to be below 10 ° C for more than 72 hours, water-stained macula will appear on the leaves. It is recommended to maintain a temperature difference between day and night of 12-25℃ for winter maintenance, and use double insulation film for protection when the cold current strikes. If temperature changes suddenly, attention should be paid to prevent cold in spring and autumn. Plants need to undergo 7-10 days of gradual environmental adaptation before being removed from the room. Damaged leaves should be pruned for frozen plants and 2000 times brassinolide solution should be used to promote recovery. 3. Scientific watering management system Key points for maintaining fleshy roots of Cymbidium hybridum have strong water storage capacity and must follow the principle of "seeing dry, seeing wet". Adopt the bamboo stick detection method: insert a 30-cm bamboo stick into the basin soil, and pour water thoroughly when it is pulled out and there is no moisture trace. When the first aid measures for rotten roots are found to be browned, immediately remove the pot and prune the rotten tissue, soak it in 50% carbendazim 800 times solution for 30 minutes, and replace it with new plant material (bark: volcanic rock =7:3). 4. Light optimization strategy The light intensity is suitable for Cymbidium hybridum. The light intensity is suitable for 15,000 - 25,000 Lux, which can be detected with a professional photometer. It is recommended to use a 50% sunshade net in spring and summer, and remove the shade in autumn and winter to ensure light scattering for 4 hours a day. Full spectrum plant fill light can be configured for indoor maintenance of the fill light system. The distance between the light and the plant is 80cm away, and the light is replenished for 6-8 hours a day. Pay attention to rotating the flowerpot regularly to ensure uniform light reception in all directions.
Systematic maintenance requires combining intelligent equipment such as temperature and humidity monitors to establish a maintenance log to record changes in environmental parameters. Regular application of special slow-release fertilizer for orchids, combined with foliar fertilizer spraying once a month, can comprehensively improve the stress resistance of cymbidium and fundamentally prevent the occurrence of yellow leaves.