Pink snakeweed

Stachytarpheta mutabilis

Common name:

Pink snakeweed

Scientific name:

Stachytarpheta mutabilis

Alternative common names:

Changeable velvet berry, pink rat tail.

This species is a perennial herb or subshrub generally growing 10-20cm tall, sometimes reaching 0.5m. This species sometimes escapes cultivation and becomes established in the wild. It can become weed-like, growing in disturbed habitats such as pastures and roadsides.

Additional Info

  • Where does this species come from?

    Mexico to northern South America and the West Indies.

    What is its invasive status in South Africa?

    NEMBA Category 3.

    Where in South Africa is it a problem?

    Mpumalanga (Kruger National Park).

    How does it spread?

    It is spread intentionally as an ornamental plant. Seeds are also spread on vehicles, in garden refuse and by rainwater.

    Why is it a problem?

    Pink snakeweed invades disturbed areas such as roadsides. It can also invade overgrazed pastures.

    What does it look like?

    Leaves: Oppositely arranged leaves are rather thick and somewhat leathery, ovate to elliptic-oblong, sometimes even lance-shaped, 5-12cm long, 2.5-6cm wide. Bracts are lance-shaped or oblong lance-shaped, 8-12mm long. Flowers: Flower spikes are stout, erect, 10-60cm tall, densely bristly. Fruit/seeds: Each fruit contains two elongated black nuts or nutlets, which could easily be mistaken for seeds. Each nut or nutlet is about 5-8 x 1.5-3mm, completely enclosed by bracts and the persistent calyx, and contains one seed.

    Does the plant have any uses?

    Used as an ornamental plant.