Mimosa pudica

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 Humble plant, TickleMe Plant, Shame plant, Sleeping grass, Prayer Plant, Touch-me-not, Makahiya (Philippines, meaning "shy"), Mori Vivi (West Indies), mate-loi (false death) (Tonga). 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". 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). The leaves are bipinnately compound, with one or two pinnae pairs, and 10-26 leaflets per pinna. The petioles are also prickly. Pedunculate (stalked) pale pink or purple flower heads arise from the leaf axils. The globose to ovoid heads are 8-10 mm in diameter (excluding the stamens). On close examination, it is seen that the floret petals are red in their upper part and the filaments are pink to lavender. The fruit consists of clusters of 2-8 pods from 1-2 cm long each, these prickly on the margins. The pods break into 2-5 segments and contain pale brown seeds some 2.5 mm long.

Plant movement
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".

Medicinal Properties
The plant lajjalu described in Ayurveda has been identified as Mimosa pudica. This plant has several alternate Sanskrit common names, including Namaskari, and Rakta Paadi.

In Ayurveda, the plant is described as a plant which folds itself when touched and spreads its leaves once again after a while. It is said to have a bitter and astringent taste, and has a history of use for the treatment of various ailments. Most commonly used is the root, but leaves, flowers, bark, and fruit can also be implemented.

Ayurvedan Properties (guna) of Lajjalu

 * Has tikta and kashaya rasa (bitter and astringent taste).
 * Has property of cold (sheetha).
 * Balances kapha, pitta.
 * Shushrutha has placed this plant in Priyangwambhastaadi gana.

Cultivation
In cultivation, this plant is most often grown as an indoor annual, but is also grown for groundcover. Propagation is generally by seed.