Paphiopedilum charlesworthii

Paphiopedilum charlesworthii (Rolfe) Pfitzer is a compact, cool-growing, single-flowered Paphiopedilum native from Assam (Mizoram) through Myanmar, northern Thailand and southwestern China (Yunnan). It grows mainly at approximately 1,200–1,600 m, often on steep limestone peaks in shaded, humid conditions.

The plant forms a compact fan of 4–6 green, strap-shaped leaves, with purple spotting commonly visible near the base of the undersides. Each growth produces a short, upright inflorescence bearing one long-lasting flower, generally around 8–9 cm across. The dorsal sepal is typically white to pink with darker veining or patterning, while the petals and pouch are lime-green to yellow-green with brown or reddish-brown markings.

Care Tips:

• Light: Provide moderate, filtered light or gentle shaded sunlight. Avoid strong midday direct sun. Paphiopedilums generally perform well around 1,000–2,000 foot-candles.
• Watering: Keep the medium consistently lightly moist, but never waterlogged. Because Paphiopedilums lack pseudobulbs, avoid allowing the plant to become completely dry for extended periods.
• Growing Medium: Use a well-draining Paphiopedilum mix based on fine or medium bark, with perlite and a moisture-retentive component. Since P. charlesworthii naturally grows around limestone, a small amount of calcareous material can also be beneficial.
• Humidity: Moderate to high humidity is beneficial, but good air circulation is essential. Avoid stagnant, wet conditions around the crown.
• Temperature: This is a cool-growing species. It prefers cooler conditions than warm-growing mottled-leaf Paphiopedilums. A general range of around 18–25°C (65–77°F) is suitable, with cooler nights beneficial. RHS lists approximately 20–25°C in summer and 18–22°C in winter.
• Fertilizing: Feed with a diluted balanced orchid fertilizer during active growth. Flush the medium periodically with clean water to prevent fertilizer-salt buildup. RHS recommends feeding approximately every third watering.
• Airflow: Provide gentle, continuous air movement, particularly when humidity is high.
• Potting: Use a relatively small pot with excellent drainage. Repot when the growing medium begins to break down, preferably after flowering or when new root growth begins.
• Flowering: The species generally flowers in late summer and autumn, with the individual flower being long-lasting. Keep light, watering and temperature stable while the bud develops.