Habitat:
Bulbophyllum rugosum is native to Peninsular Malaysia, Borneo, and Sumatra. It inhabits lowland and lower montane forests at elevations from 300 to 1300 metres. This species grows as an epiphyte on trunks and large branches of mature trees in primary and old secondary forests. It is often found in hill dipterocarp forest, swampy forest margins, and on ridges where humidity remains high and temperatures are warm year-round. The plant is adapted to humid conditions with frequent rainfall and filtered light beneath the forest canopy.
Description:
Bulbophyllum rugosum is a creeping epiphytic orchid that forms compact mats of closely spaced pseudobulbs connected by slender rhizomes. Each pseudobulb is ovoid to slightly cylindrical, about 1–2 cm long, and topped with a single leathery, oblong to elliptic leaf measuring 10–20 cm long and 2–4 cm wide. The inflorescence emerges from the base of the pseudobulb and is typically 10–18 cm long, carrying a loose raceme of several small flowers. Each flower is about 1–1.3 cm across, yellowish to ochre-yellow butvmostly white. The sepals are thick and prominently wrinkled (rugose), a key feature of this species. Petals are smaller and often reflexed. The mobile lip is small, aiding in its adaptation for fly pollination. 
Cultivation:
Bulbophyllum rugosum grows best in warm, humid conditions with bright, filtered light or light shade. Ideal daytime temperatures are 20–28°C, with nighttime temperatures between 14–18°C. Humidity should remain at 70–90%, with good air circulation. It is well-suited to shallow baskets or small pots filled with a coarse, moisture-retentive mix such as fine bark with sphagnum moss. The roots should stay moist; allow only slight drying between waterings. The substrate pH should be slightly acidic (5.5–6.5). Fertilize every 2–4 weeks during active growth with a dilute balanced orchid fertilizer.
Specifications:
Plant Size:
Plant Family: Orchidaceae
Plant Passport: Bulbophyllum rugosum B 140084 C 10249 D GB