What Does It Look Like?
What is it?
Common Sensitive Plant (Mimosa pudica) is a prickly long-lived herb or small shrub, sometimes becoming woody, with a creeping or sprawling habit. It usually only grows to 15-50 cm tall, but can reach up to 1 m in height when supported by other vegetation. The reddish-brown to purplish coloured stems tend to become woody with age. These stems are rounded, multi-branched, and armed with scattered curved prickles that are 2.5-5 mm long. The leaves are compound (made up of more than one leaflet), alternately arranged, and have leaf stalks that are 15-55 mm long. They consist of one or two pairs of branchlets that often have a covering of stiff, prickly bristles. Each of these branchlets is 5-8 cm long and has 10-25 pairs of small dark green leaflets arranged along them. These leaflets are elongated or oblong in shape and are 6-15 by 1-3 mm in size and have slightly hairy margins. The leaves are very sensitive and fold up when touched and or at night (Navie 2004).
The pink or purplish-pink coloured flowers are arranged in small, fluffy, globular or egg-shaped clusters that are 9-15 mm across. They resemble 'pom-poms' and are borne on bristly stalks that are 12-25 mm long. Individual flowers have four tiny petal lobes and four long stamens that give the flowers their fluffy appearance.
The oblong and flattened seed pods (fruit) are 10-25 x 3-6 mm in size and are clustered together at the end of stalks which emanate from the leaf forks. These pods contain 1-5 seeds and their edges are covered in stiff, almost prickly bristles. They are initially green in colour, but turn brown and break apart into one-seeded segments when mature. Seeds are light brown in colour, somewhat flattened 2.5-3 mm long, and have a finely textured surface (Navie 2004).
For further information and assistance with identification of Common Sensitive Plant contact the herbarium in your state or territory.
Purple or Pink
Growth form (weed type/habit)
Where it currently grows? Preferred habitat
Common Sensitive Plant is a weed of wetter coastal areas mainly in tropical and sub-tropical regions. It is mostly found in plantation crops, disturbed sites, pastures, waste areas, parks, lawns, gardens and along roadsides (Navie 2004).
Are there similar species?
Common Sensitive Plant is very similar to Mimosa (Mimosa pigra) and Giant Sensitive Plant (Mimosa diplotricha var. diplotricha), which both also produce pink globular flower clusters and have prickles. Mimosa is a large shrub with an upright growth habit that has large much-branched leaves with 6-16 pairs of branchlets. It produces relatively large pods 3-8 cm long that contain 14-26 one-seeded segments. Giant Sensitive Plant is an upright shrub or climbing plant that has much-branched leaves with 4-9 pairs of branchlets. It produces relatively small pods 1-3.5 cm long that contain 3-5 one-seeded segments.
Common Sensitive Plant is also relatively similar to the slightly weedy Native Sensitive Plant (Neptunia gracilis) which is, however, a relatively small plant, with a creeping growth habit, and has only one or two pairs of branchlets. Further, it does not have prickles along its stems, has yellow flowers, and its pods do not separate into one-seeded segments when mature (Navie 2004).