What's Blooming

Jenisch's Stanhopea (Stanhopea jenischiana)

Secret Garden, Cloud Forest

Jenisch's Stanhopea (Stanhopea jenischiana) is a fascinating orchid species native to the cloud forests of Colombia, Ecuador and Venezuela. This orchid thrives in humid, shaded environments, usually growing as an epiphyte on trees at elevations ranging from 1,000 to 2,000 meters.

A member of the orchid (Orchidaceae) family and genus Stanhopea, which honours Philip Henry Stanhope, a 19th-century British horticulturist who contributed significantly to botany, this species is renowned for its unique floral structure and captivating cinnamon-like to fruity scent. Possibly triggered to start flower spike production by experiencing a cooler and drier conditions, the long and pendant inflorescences of Jenisch's Stanhopea emerges from the base of the plant, producing multiple large, fleshy flowers. Each bloom is a masterpiece, with a yellow base adorned with bold, reddish-brown or maroon markings like leopard spots. The flowers are large, typically 6 to 10 centimetres wide, with an elaborate lip (labellum) that plays a crucial role in attracting pollinators. 

The structure of the flower is meticulously designed to facilitate pollination by orchid bees. The large, showy lip acts as a landing platform for the orchid bees, attracted by the strong floral fragrance. As the bee climbs on the lip, its back brushes against the pollinia - compact packets of pollen, one of the unique characteristics of orchid flowers - which adheres to the bee’s back. When the bee flies away and visits another flower of the same species, its back inadvertently brushes against the stigma, depositing the pollinia and completing the pollination process.

The comparison between the front view and side view of a Jenisch's Stanhopea flower. The anther cap covers the pollinia and will drop easily after being brushed by the bee’s back, as the bee climbs on the lip (labellum). Then the viscidium (a sticky pad) will adhere the exposed pollinia onto the back of the bee, so the bee can bring the pollinia to the next flower. Please note the relative position of the pollinia, lip and stigma, which facilitates the pollination process. To see some wonderful videos and diagrams showing exactly how the bees interact with the orchid and pick up or deposit pollen, visit this resource page by the Manchester Museum.

This intricate design of Stanhopea flowers has fascinated scientists for centuries and serves as a classic example of co-evolution, illustrating how the orchids and the pollinators have evolved together over time to create such highly specialized relationships. The precision of this system is so remarkable that only certain specific orchid bee species (Euglossine bees) can successfully pollinate each species of Stanhopea! For Stanhopea jenischiana, it is the males of the bee species Eulaema bomboides, attracted to the flowers by their sweet scent. As with other orchid bee species, they may collect scented compounds from these flowers for use in attracting or signaling to female bees.  

Come to Secret Garden in Cloud Forest and witness the bizarre and magnificent flowers of Stanhopea jenischiana! This is the first time this particular plant is flowering after we received it some six months ago and each flower only lasts 3-4 days.

This article is part of our What's Blooming series.