Phalaenopsis cultivation techniques in Northwest China
July 02 10:31:18, 2025
Phalaenopsis orchids, commonly known as moth orchids, are perennial epiphytic plants belonging to the Orchidaceae family. Native to regions such as the Philippines, the Malay Peninsula, and Taiwan, China, they are highly valued for their ornamental beauty and often called the "Queen of the Sea Orchid." These plants thrive in temperatures ranging from 22°C to 28°C during the day and 18°C to 20°C at night. They require a humidity level between 70% and 80%. Light requirements vary depending on the growth stage: seedlings need less than 10,000 Lx, medium-stage plants require around 10,000 Lx, and flowering plants benefit from 15,000 to 20,000 Lx or more. The entire growth cycle from bottle seedlings to blooming can be divided into five stages: bottle seedlings, young seedlings, middle seedlings, large seedlings, and flowering seedlings.
When cultivating Phalaenopsis, it's essential to use well-draining substrates. Common materials include sphagnum moss, peat moss, charcoal, coconut fiber, vermiculite, and perlite. A good substrate promotes healthy root development and prevents root rot. Before planting, the medium should be thoroughly sterilized to eliminate pests and diseases. Two popular mixtures are used: one combines 1/3 charcoal with 3/4 sphagnum moss, while the other layers charcoal, gravel, and coconut fiber, each taking up 1/3 of the pot. The first method is most commonly used due to its effectiveness in preventing root rot caused by waterlogging.
For pots, opaque containers are recommended. Plastic pots are widely available and affordable, but I believe Zisha (clay) pots offer better air circulation and moisture control. The pot size should match the plant's size—typically 6–8 cm in diameter for large seedlings. Too small a pot restricts root growth, while too large a pot leads to wasted media and an unbalanced appearance.
Temperature management is crucial. In summer, keep indoor temperatures between 20°C and 28°C, ensuring good ventilation. In winter, maintain a minimum of 18°C. High temperatures can cause wilting, so cooling measures may be necessary. Humidity should be kept between 70% and 80%, and watering must be done carefully. Overwatering can lead to bacterial infections and root rot. Water when the substrate is slightly dry, using clean water like well water, rainwater, or river water at 15–18°C. Avoid cold tap water directly; if needed, let it sit for 1–2 days before use. During flowering, avoid wetting the flowers themselves.
Light requirements change throughout the growth cycle. Seedlings need less than 10,000 Lx, while mature plants require higher light levels. Excessive light during the early stages can damage young plants. Fertilization is also important. Since the growing medium lacks nutrients, regular feeding is necessary. Organic options like soybean residue can be soaked and filtered for use. Inorganic fertilizers are convenient and effective, especially those with high phosphorus and potassium content for blooming.
In the early stages, small seedlings should not be fertilized for the first week after being removed from the bottle. Instead, apply carbendazim for disinfection and root growth powder every two days. After a week, use a diluted fertilizer (30:10:10) every other week. As the plant grows, adjust the fertilizer ratio accordingly, focusing on low nitrogen and high phosphorus/potassium. For large seedlings, a balanced 20:20:20 fertilizer is ideal. During flowering, use a high-phosphorus formula (10:30:20) every 15 days to support bud development.
Pest and disease control are also critical. Common issues include soft rot and gray spot. Infected plants should be isolated immediately. Remove affected areas, disinfect with alcohol, and spray with mancozeb or carbendazim. For pests like scale insects and aphids, use a 50% emulsion of pine oil diluted to 1000 times. Regular monitoring and proper ventilation help prevent outbreaks.
Overall, successful Phalaenopsis cultivation requires attention to temperature, humidity, light, watering, fertilization, and pest control. With proper care, these beautiful orchids can thrive and bloom beautifully.
Author: Department of Landscape Architecture, Gansu Forestry Vocational and Technical College