Toothbrush Orchid (Dendrobium secundum)

Dendrobium secundum in bloom. Are you able to spot the small, pink blooms from afar?

Dendrobium secundum is an epiphytic orchid species native to a wide range stretching from Bangladesh to western and central Malaysia, including the Andaman Islands, Borneo, Cambodia, Laos, Myanmar, Thailand, Vietnam, and Malaysia, through East Indonesia. It can be found thriving in semi-deciduous and deciduous lowland forests and savanna-like woodlands, typically at elevations from sea level up to 700 meters.

The ends of the leafless old canes of the toothbrush orchid are where the flower stalks eventually emerge from.

Widely known as the toothbrush orchid, its flowers are lined up neatly on the top of a laterally oriented inflorescence, reminiscent of the bristles on a toothbrush. Up to 50 waxy flowers can appear on a single inflorescence, which can grow up to 12.5 cm long! With a distinctive orange labellum in contrast with pink sepals and petals, each flower is only about 0.6 cm wide, and 1.5 cm long, which is on the smaller side of a typical Dendrobium bloom, such as Dendrobium speciosum whereby the diameter of the flowers can grow up to 8 cm wide and 7 cm long!

Closeup of the flowers of Dendrobium secundum.

With its tubular, pink flowers, it is likely to be pollinated by birds, potentially a sunbird, as several Dendrobium species are sunbird-pollinated. The inflorescences mostly appear on leafless older canes, after shedding its leaves from a period of active growth. It also features cane-like pseudobulbs that can reach up to 50 to 70cm in length, with young canes growing upright, and subsequently becoming gracefully pendulous, arching under the weight of their growth and blooms.

Come and spot the toothbrush orchid in bloom! Look closely – they can be found in the Heritage Gardens, growing on the Chinese pistachio (Pistacia chinensis) opposite the restrooms between the Malay and Chinese Gardens!

Written by: Ng Yu Qin, Senior Horticulturist, Research and Horticulture

Yu Qin is always looking for ways to pick up new skills and put them to use. She spends most of her time with orchids and enjoys learning something new about them every day!