Quietly trailing the soil with slender stems, Mimosa pudica is an unassuming herb. While it does not invite attention, it responds dramatically to the touch. At a light caress, its fern-like leaves will fold inward; a gentle thrust will collapse the petiole. Mimosa pudica (Bashful Plant) is the introvert of the garden, yet, with a coy choreography that is curiously beautiful, it is impossible not to touch, and has fascinated botanists for centuries.
Video credit: Anna Laurent and Jamal Penjweny
It is not known why the plant has evolved a tendency to curl inward (it is speculated that the unexpected motion deters predators or casts away insects looking for a steady perch), it baffled Charles Darwin, who noticed that the plant similarly retreats at night. In The Power of Movement in Plants (1880), Darwin documented a prolonged study of its nocturnal movements.
While the adaptive benefits of its movement are unknown, Mimosa pudica has nonetheless acquired a distinct character portrait, by way of its many epithets. Carl Linneaus was the first to name the species. In Species Plantarum (1753), he called it pudica, Latin for "bashful" or "shrinking." Since then, the South American native has travelled internationally, and received a list of other names. In Indonesia, it is called "putri malu" (shy princess); in India, "thottavaadi" (wilts-by-touch); in Singapore, "thotta-siningi" (cry-baby). And, in Kurdistan, where I encountered the plant, it is called "fedî" (shame).
In the video above, you can see the plant curling as it is stroked.
Anna Laurent is a writer and producer of educational botanical media. Photographs from her forthcoming field guide to Los Angeles are available for exhibition and purchase at the author's shop.