Ferns that curl and close at the touch of a finger provide a hint of magic in a garden or a pond or other habitats where they grow. They are ideal plants to interest children in the wonderful world of gardening. As it happens, these particular ferns thrive in many countries, mostly in tropical climates.
Native to tropical America, Mimosa pudica means "bashful" or "modest" in Latin. The reason for this unusual name is that its dark green, bipinnate leaves immediately fold closed against the branches when touched by the human hand. "Noxious Weeds of Australia" includes a detailed profile of Mimosa pudica, also considered a weed in other parts of the world. For example, it is daven kagat-kager in Indonesia, dedinnaru in Sri Lanka, dorme-dorme in Brazil, dormidera in Cuba and huya-huya in the Philippines. Reproduced by seed, Mimosa pudica pops up as a sprawling shrub in cultivated fields, on roadsides and in gardens, and grows very quickly. Watch out for the prickly thorns on its long and abundant branches, which also display small, purplish pink flowers that bloom continuously. Mimosa pudica germinates predominantly during the wet season. A single plant produces between 600 and 700 seeds in a single season, easily dispersed. According to the Asia Pacific Medicinal Plant Database website, Mimosa pudica was a traditional antidote to insomnia in Indonesia, Malaysia and Thailand and has other medicinal uses in Southeast Asia.
Giant Sensitive Fern
According to the Flora of Zimbabwe website, you'll find the giant sensitive fern (Aescchynomene Fluitans) floating gracefully on the water's surface of rivers, large ponds, and floodplains, buoyed by a foamy tissue that surrounds the plant's stems. Classified as rare, it exhibits attractive yellow flowers that grow to between 6 inches and 10 inches, usually between summer and fall. Touch the leaves and they close. Places where you'll find the giant sensitive fern include Angola, Botswana, the Democratic Republic of the Congo (DRC), Namibia, western Tanzania, and Zambia.
The sensitive plant (Neptunia oleracea) thrives in U.S. Department of Agriculture hardiness zones 9 to 11, producing clusters of yellow summertime flowers that usually bloom in August. It is a creeping plant that needs full sun to partial shade to be at its best. It can also grow in a pond as a floating plant. Its alternate, twice pinnate, fernlike leaves close at the touch. The sensitive plant is a member of the Leguminosae or Fabaceae, pea or bean, family.