What's Blooming

Evergreen Velvet Bean (Mucuna sempervirens)

Cloud Forest, Treetop Walk

Like Jack’s magic beanstalk, these climbing, twisting, creeping vines can grow high up into tree canopies over 25m tall! While the thick, woody vines of the charmingly rhyming evergreen velvet bean (Mucuna sempervirens) can be easily overlooked, in full bloom, hundreds or even thousands of large, showy, purple flowers hang in clusters sprouting directly from the main stem or largest branches. Our specimens in Cloud Forest only started flowering three to four years ago and are much younger and smaller, currently sporting a much more modest two inflorescences!  

Native to the forest of Assam, India, to Central and South China and parts of Myanmar and Japan, this woody, evergreen vine is a member of the Mucuna genus, comprising about 113 different species, and a member of the legume family (Fabaceae), producing flowers 5 to 7cm long and pods resembling but much larger than our edible peas and beans! 

Unlike many flowers that are pollinated by insects such as butterflies, bees, and flies, the larger purple flowers of the evergreen velvet bean are pollinated by relatively large mammals: squirrels, rats, and civets, that also have play a dual ecological role as the plant’s seed distributors, eating, hording, and scattering the seeds.  

The large flowers of the evergreen velvet bean have some hidden secrets! First is a strangely scented nectar, to attract and entice its mammal pollinators, such as squirrels, large rats, and civets. To get at the nectar inside the flowers, these animals squeeze the hook-like keel petals with their nose or face, resulting in a second surprise: the keel petals exploding open to expose the anthers and stigma, showering pollen onto their furry friends! If pollination and fertilization are successful, the ovary of each flower will develop into a 30 to 60cm long pod bearing four to twelve large, disc-shaped, dark brownish red, inedible seeds up to 3cm in diameter. 

Like its furry pollinators, each flower is capped with a hairy calyx of brittle, stiff golden hairs that can cause itching if you rub against it, so look but don’t touch! These hairs may serve to protect the developing flower buds from being eaten before the flowers have a chance to bloom.  

After finding the flowers in the photo above, you’re ready to come and see them up close and in-person! Catch this uncommon species, the evergreen velvet bean, in rare bloom at the end of Treetop Walk at the Cloud Forest mountain! 

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