Papilionanthe teres aka Terete Vanda

Papilionanthe teres requires frequent watering, especially during the active growing season. In summer, water daily, allowing the roots to dry quickly between waterings. In winter, reduce watering but keep the plant slightly moist—never let it dry out completely. Use rainwater, distilled water, or reverse osmosis water with a pH between 5.0-6.5, as this orchid is sensitive to minerals and salts in tap water. Good drainage is essential to prevent root rot.

As an epiphyte, Papilionanthe teres does not grow in traditional soil. It thrives in a very coarse, fast-draining medium of bark chunks and charcoal pieces (3-4 cm in size), or can be grown mounted on cork or tree fern, or in hanging baskets with no medium at all. Many growers successfully cultivate it tied to poles or logs where it can develop its aerial roots freely. Wire mesh tubes can help manage its scrambling growth habit while providing excellent air circulation.

Papilionanthe teres requires very high light intensity—ideally full sun. This is one of the few orchids that thrives in direct sunlight, needing 50,000-60,000 lux to initiate flowering. In very hot or dry climates, provide some afternoon shade to prevent leaf scorch. Insufficient light is the main reason this orchid fails to bloom. A south-facing window or greenhouse with maximum sun exposure is ideal.

Papilionanthe teres requires high humidity between 70-90%, with constant air movement. In its native habitat, it experiences monsoon conditions with heavy rainfall and humid air. Provide excellent ventilation to prevent fungal issues—stagnant humid air is harmful. Use a humidifier, humidity trays, or group with other plants. In dry climates, misting can help but should not replace proper watering.

Papilionanthe teres thrives in warm to intermediate temperatures. During the growing season (spring through autumn), maintain daytime temperatures of 24-32°C (75-90°F) with nighttime temperatures around 15-20°C (59-68°F). In winter, slightly cooler temperatures are acceptable but night minimums should not drop below 12°C (54°F). Despite originating from Himalayan foothills, it does not tolerate frost and is susceptible to cold damage.

During active growth (spring through summer), fertilize weekly with a diluted orchid fertilizer at 1/4 to 1/2 the recommended strength. In late summer and autumn, switch to a fertilizer with reduced nitrogen and increased phosphorus to encourage flowering. Reduce or suspend fertilizing during winter when growth slows. Always water before fertilizing to prevent root burn from concentrated salts.

Papilionanthe teres is propagated through stem cuttings. Take a cutting at least 20 cm (8 inches) long that includes aerial roots and several nodes. Allow the cut end to dry for a day, then place in a humid environment with bright light and good air circulation. Keep the cutting warm and misted until new roots develop. Alternatively, commercial propagation uses seed germination in vitro or tissue culture (micropropagation).

Papilionanthe teres produces large, showy, fragrant flowers measuring 7-10 cm (3-4 inches) in diameter. Blooms appear on lateral inflorescences carrying 3-6 flowers each. The petals are white to rose-pink with a distinctive trilobed lip marked with deep pink and yellow. Flowering peaks in late spring and early summer, coinciding with monsoon rains, though plants can bloom year-round under optimal conditions. Individual flowers last about one week. High light intensity is essential to initiate flowering.

Papilionanthe teres develops long, scrambling stems that can reach up to 2 meters (6-7 feet) in length. The plant has a branching habit and can form sizeable clusters over time. Its distinctive terete (cylindrical) leaves are fleshy and measure 8-20 cm long. The aerial roots extend from nodes along the stem. Due to its scrambling growth habit, it's often grown in wire mesh tubes or trained on supports to manage its size.

Papilionanthe teres is native to South and Southeast Asia, with a range extending from Nepal through the eastern Himalayas, northeastern India (Assam), Bangladesh, Myanmar, Thailand, Laos, Vietnam, peninsular Malaysia, Singapore, to southern China (Yunnan). It also occurs in the Andaman Islands. The species grows as an epiphyte on tree branches in open forests and forest margins, from near sea level up to about 800 meters elevation.

Papilionanthe teres is relatively resistant to pests and diseases when grown under optimal conditions. The main concerns are weevils, which cause flower streaking and require preventive insecticide applications every 15-20 days during flowering. Viral infections can occur, showing as brown spots or discoloration—infected plants should be isolated as there is no cure. Root rot from overwatering or poor drainage is a common issue. Good air circulation helps prevent fungal problems.

Repot Papilionanthe teres every 2-3 years or when the growing medium begins to decompose and drain poorly. Choose a slightly larger container and use fresh bark/charcoal mix. Repot in spring when new growth begins. Handle roots carefully as they are easily damaged. After repotting, reduce watering for a few weeks until new roots establish. Many growers prefer mounted cultivation or basket culture to avoid repotting stress altogether.

Papilionanthe teres occurs in several forms. The type form has pink and white flowers, while the alba form (f. candida) produces pure white blooms. The variety 'Andersonii' is historically significant as the pod parent of the famous hybrid Papilionanthe 'Miss Joaquim' (P. teres × P. hookeriana), which is Singapore's national flower—making Singapore the only country with a hybrid orchid as its national floral emblem.

Papilionanthe teres can be grown outdoors year-round in tropical and subtropical climates (USDA zones 10-11) where temperatures stay above 12°C (54°F). In its native range, it thrives tied to tree branches or posts outdoors. In cooler climates, grow it outdoors during warm summer months and bring inside when temperatures drop. The plant does not tolerate frost. Outdoor cultivation requires full sun, high humidity, and protection from cold winds.

Papilionanthe teres is considered non-toxic to cats, dogs, and humans. Orchids in the Orchidaceae family are generally safe for pets according to the ASPCA, and Vanda orchids (the closely related genus) are specifically listed as non-toxic. While ingestion may cause mild stomach upset, there are no serious toxicity concerns. However, fertilizers and pesticides applied to the plant can be harmful, so use pet-safe products if pets have access to the plant.

Papilionanthe teres produces fragrant flowers. OrchidSpecies.com describes the blooms as 'large, showy, fragrant flowers.' The fragrance is most noticeable during the day when the flowers are fully open. Not all plants may be equally fragrant, and environmental conditions can affect scent intensity.

In traditional medicine in Nepal, a paste made from Papilionanthe teres is applied externally to treat dislocated bones. This ethnobotanical use is documented in the Plants of the World Online (Kew Gardens) database. However, there is limited scientific research validating these traditional uses, and the plant is primarily cultivated for ornamental purposes.