The
Sensitive plant (
Mimosa pudica L.) is a creeping annual or perennial herb often grown for its curiosity value: the compound leaves fold inward and droop when touched, re-opening within minutes.
Mimosa pudica is native to Brazil, but is now a pantropical weed. Other names given to this curious plant are TickleMe Plant tm, Humble plant, Shame plant, Sleeping grass, Prayer Plant, Touch-me-not, Makahiya (Philippines, meaning "shy"),
Mori Vivi (West Indies),
mate-loi (false death). The
Chinese name for this plant translates to "shyness grass". The species epithet,
pudica, is Latin for "bashful" or "shrinking", because of its curious nature and easy procreation. Its Sinhala name is
Nidikumba, where 'nidi' means 'sleep'. The seeds are currently marketed to children under the name TickleMe Plant tm. The stem is erect in young plants, but becomes creeping or trailing with age. The stem is slender, branching, and sparsely to densely prickly, growing to a length of 1.5 m (5 ft).mm long.
Mimosa pudica is well known for its
rapid plant movement. In the evening the leaflets will fold together and the whole leaf droops downward. It then re-opens at sunrise. This type of motion has been termed
nyctinastic movement. The leaves also close up under various other stimuli, such as touching, warming, or shaking. The stimulus can also be transmitted to neighbouring leaves. These types of movements have been termed
seismonastic movements. The cause is a loss of
turgor pressure. The movement is caused by "a rapid loss of pressure in strategically situated cells that cause the leaves to droop right before one’s eyes"
Caleb (and the others) think it is fascinating! We decided to buy one and bring it home... it stays in Caleb's bedroom and will be his job to take care of.
