Mimosa pudica

Mimosa pudica
Botanic Garden Meise

Mimosa pudica or sensitive plant is a nice little plant whose leaves close when touched.

Robert Hooke (English scientist, 1635-1703) was one of the first to study the movement of Mimosa pudica. He suggested that these plants could have nerves and tissues, like animals.

Later, it was discovered that the folding of the leaves is a result of the inward movement of water and the mechanism of the process is now well documented. A stimulus, such as touching or air movement, triggers chemicals in certain areas of the stem through which water leaves the cell and the cell immediately collapses.

This fast motion response of the plant likely serves as a defense against herbivores that are deterred or, if they are small, are driven away from the plant.

The leaves are also folded at night.

This may not be a plant that with huge ornamental value or prized in a collection, but it is really fun and not just for kids.

It can be grown outdoors as an annual or indoors as a houseplant.

In the tropics, it’s a weed.

Description:

Mimosa pudica is an annual or perennial small shrub of 50-70 cm high.

The stems are thinly covered in spines 2-2.5 mm long, sometimes bristly or nearly bare.

The leaves are alternate, bipinnate, have no spines and are very sensitive to touch. The rachis is 1.5-5.5 cm long, the pinnae are subdigitate. There are 10-26 pairs of elongated leaflets per pinnae, 6-15 cm long and 1.2-3 mm wide .

The flowers are pink and lilac or stand in ovoid stalked heads of about 1 cm in diameter. A cluster of 1-5 flower heads appears in the leaf axil. The lilac or pink part are actually the stamens. The sepals and petals are miniscule.

The fruit is a pod of 1.8 cm long and 3-5 mm wide, densely bristly, in clusters, with spines along the edges.

Like many other legumes, the sensitive plant grows in association with nitrogen-fixing bacteria that live within its root nodules. These bacteria convert atmospheric nitrogen into a form that promotes the growth.

Usage:

Ornamental, medicinal, green manure, fodder…

Nomenclature:

Common names:

Sensitive plant, shame weed, shameful plant, touch-me-not, humble plant

Synonymes:

Mimosa hispidula, Mimosa pudica var. hispida, Mimosa pudica var. tetrandra, Mimosa pudica var. unijuga, Mimosa tetrandra, Mimosa unijuga

Etymology:

Mimosa: from the Latin mimus (mime)
Pudica: from the Latin pudīcus (modest, chaste)

Origin:

Tropical America



Habitat:

Open waste land in tropical vegetation

Hardiness:

USDA zone 9-11

Mimosa pudica flowers

Mimosa pudica flowers

Care:

Soil:

Well drained nutritious soil

Light:

Light

Water:

Keep the soil evenly moist but not wet

Feed:

During the growth period give every 2 weeks a high potassium (K) fertilizer

Temperature:

Room temperature: 20-24 ° C
At colder temperatures the plant reacts less to touch.

Propagation:

Seed

Sowing instructions:

  • indoors all year
  • the seed coat is hard, it is recommended to scarify the seeds with a sharp knife
  • soak the seeds 1 night in water
  • plant the seeds not too deep into moist sowing substrate
  • keep at room temperature
  • germination time: a few days to 1 week, sometimes even just one day

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