Biophytum sensitivum

A miniature palm-like herb from tropical Asia, with a single unbranched stem topped by a rosette of feathery, pinnate leaves that fold shut when touched and close again each night. Two things make it stand out in a terrarium: a slow circadian leaf-folding rhythm, and an immediate seismonastic response to touch — brush its leaves and they fold shut, reopening a few minutes later. It is short-lived, typically completing its life cycle in 12–18 months before setting seed and dying, but the explosive seed pods scatter seeds into the substrate and a healthy terrarium can sustain a self-seeding population. It does best kept consistently moist in high humidity, 15–28 °C, with bright indirect light.