First of all, what is a sensitive plant? It is a plant that has the incredible ability to react to external stimulation by performing a more or less rapid movement. This spectacular reaction results either from a phenomenon of protection against herbivorous animals or from a phenomenon linked to the weather, but it can also be an adaptation to their surrounding environment.
Mimosa pudica is probably the most famous sensitive plant. These alternating leaves have the particularity of folding back almost instantly at the slightest shock, which in botanical jargon should be called thigmonasty. This is one of the most spectacular movements in the plant kingdom. As with other sensitive plants, the fallback movement provides protection from bad weather or predators. Once calm has returned, the leaves resume their bearing. Specialized “motor” cells located on the axis of the leaf and the petiole are responsible for this by a phenomenon of water migration, the stimulated cell drives out the water, which causes the leaves to fold.
There are other sensitive plants, such as Codariocalyx motorius, which is a tropical species from Asia. This unusual and rare plant is known for its rapid movement of leaves, perceptible to the naked eye, which gives the impression that it is dancing, which has earned it the common name of “Dancing plant”. Schrankia uncinata is a sensitive plant native to the southeastern United States and which, like Mimosa pudica, has the ability to react to external stimuli. But this one has the unique characteristic of being hardy down to around -5°C.