The Tickle Me plant is called Choi Moi (pronounced chouyi mouyi) in Urdu and grows wild in Pakistan. Children love to find it and touch its leaves which immediately curl up tight. For this reason it is also called the sensitive plant, the humble plant, Touch Me Not, and probably a lot of other names all relating to its shrinking qualities; even the Latin name pudica means shy.
There is of course a scientific explanation for this shrinking phenomenon, and this is that the stem has some areas in it which release chemicals which force water out of the cells causing them to collapse when the leaves are touched. The plant has a nyctinastic movement which means that the leaves close at night or in response to darkness, and open when exposed to light. However it captivates young children and is grown in the house in Pakistan to entertain them.
Mimosa pudica is a pan-tropical weed and an invasive species in some parts of the United States, but before you uproot it, if it’s invading your garden, you may want to consider its health benefits. On the other hand if you grow crops that need to be hand-picked it can be a nuisance and is a problem to growers of tomatoes, sugar cane, papaya and coffee for example. However even for those farmers it has some benefits as the root nodules are nitrogen fixers so help the soil regain its balance.
This plant has been used in traditional medicine on the Indian subcontinent for centuries, and the roots have been used for their wound healing properties, as a febrifuge (to relieve fevers), as a diuretic and for their antispasmodic and astringent properties. A decoction of the leaves or an infusion has been used to treat asthma as they have expectorant qualities. As a poultice they are used to relieve glandular swellings, and the bruised leaves are good to put on bruises. They are also used to relieve anxiety and hypertension and are a muscle relaxant according to traditional healers or hakims. In some parts of India the plant is used as a contraceptive for women, and for uterine problems. In China the plant is used to treat depression and anxiety. Although the leaves and roots are primarily used in traditional medicine the flowers and fruit (seeds) are also used.
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The seeds have apparently also been used as a coffee substitute, and in Ayurvedic medicine the plant is used to treat impotence and general debility. It is also used in the treatment of diarrhoea and dysentery, skin problems and bronchial complaints.
If it grows in your garden, don’t be too hasty about getting rid of it.