About Alternanthera brasiliana (L.) Kuntze
Alternanthera brasiliana (L.) Kuntze is an erect, sprawling herbaceous plant. It can reach up to 3 metres in height, though cultivated specimens usually grow to less than 1 metre. Its stems range in colour from red and green to purple; young stems are finely covered with hairs, while older stems become nearly hairless. The plant bears opposite leaves that measure 1–10 cm long and 0.7–5 cm wide, and are typically purple-speckled or a luminous reddish-purple. In regions with slightly cool winters, it can lose some of its leaves, making it partially deciduous. Its vanilla-coloured, pom-pom-shaped small flowers are arranged in compact clusters 7–20 mm long, borne in the upper leaf axils. These clusters are rounded to slightly elongated, and grow on stalks that are usually 3–10 cm long. The plant can flower at any time of year, but it flowers most frequently in winter in temperate and cooler subtropical climates. It produces very small brown fruit 1.5–2 mm long, which holds a single seed that is usually concealed within persistent old flower parts. This species is native to Brazil, Peru, Ecuador, Colombia, Venezuela, the Guyanas, Nicaragua, Belize, Guatemala, Mexico, northeastern Argentina, Trinidad and Tobago, Aruba, and the Windward Islands. It has become naturalised in wild areas and cultivated land in West Africa, coastal districts of northern and eastern Australia, Florida, South Africa, several Pacific Islands, and on shaded ravine slopes and along creeks in Java. Like most joyweed species, Alternanthera brasiliana is classified as an environmental weed in Queensland, New South Wales, the Northern Territory, and Western Australia. The plant is grown as an ornamental, with many existing cultivars including 'Purple Prince' and 'Little Ruby', which are classified as cultivars of Alternanthera brasiliana var. villosa. It is often harvested from the wild for local use as food and medicine, where it is employed as an antiviral and anti-diarrhoea treatment. It grows best in full sun in moist, well-drained soil, and spreads readily through self-seeding. It can also be easily propagated from stem cuttings.
