Phalaenopsis cultivation techniques in Northwest China
July 02 10:39:41, 2025
Phalaenopsis orchids, also 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, these orchids are highly valued for their ornamental beauty and are often referred to as the "Queen of the Sea Orchids." They thrive in temperatures between 22°C and 28°C during the day, with nighttime temperatures ranging from 18°C to 20°C. The ideal humidity level is 70% to 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 growth cycle of Phalaenopsis can be divided into five stages: bottle seedlings, young seedlings, middle seedlings, large seedlings, and flowering seedlings. Proper cultivation begins with selecting the right growing medium. Common substrates include sphagnum moss, peat moss, charcoal, coconut fiber, vermiculite, and perlite. These materials provide good aeration and drainage, which helps prevent root rot. Before planting, the substrate should be thoroughly sterilized to eliminate pests and pathogens.
A popular method involves placing 1/3 charcoal at the bottom of the pot, followed by 3/4 of the pot filled with sphagnum moss. Another mix combines charcoal, gravel, and coconut fiber in equal parts. This ensures proper drainage and avoids waterlogging. For pots, opaque containers are preferred, with plastic pots being widely used due to their affordability and lightweight nature. However, Zisha (clay) pots are often considered superior for promoting healthy root development.
When choosing the container size, it's important to match it to the plant’s size. A 6 to 8 cm diameter pot is typically suitable for large seedlings. Too small a pot restricts root growth, while too large a pot may lead to excess moisture retention and an unbalanced appearance.
Temperature control is crucial. In summer, keep indoor temperatures between 20°C and 28°C, ensuring good ventilation. In winter, maintain a minimum of 18°C, using heating if necessary. High humidity is essential, so aim for 70% to 80% air humidity. Watering should be done carefully—avoid overwatering, as this can lead to root rot. Water when the substrate is slightly dry, using clean water at 15–18°C. Avoid cold tap water; if necessary, let it sit for 1–2 days before use.
Light exposure varies throughout the growth stages. Seedlings require less light, while mature plants need more. During flowering, high light intensity is beneficial. Fertilization is key, especially since the growing medium lacks nutrients. Organic options like soybean residue can be soaked and diluted before application. Inorganic fertilizers are also effective, with different formulations used at various growth stages.
For seedlings, avoid fertilizing for the first week after transplanting. Instead, apply carbendazim for disinfection and use rooting powder to encourage root growth. After one week, apply a nitrogen-rich fertilizer (30:10:10) every other week. As the plant matures, adjust the fertilizer ratio to lower nitrogen and higher phosphorus and potassium. During the flowering stage, use a bloom booster (10:30:20) every 15 days.
Pest and disease management is also important. Common issues include soft rot and gray spot. If detected, isolate the affected plant and treat the wound with alcohol, then spray with mancozeb or carbendazim. For pests like scale insects and aphids, use a 50% emulsion of pine oil diluted 1000 times.
In summary, successful Phalaenopsis cultivation requires attention to temperature, humidity, light, watering, and proper fertilization. With the right care, these beautiful orchids can flourish and produce stunning blooms.
Author: Department of Landscape Architecture, Gansu Forestry Vocational and Technical College