Watsonia meriana var. bulbillifera

Bulbil watsonia

Family: Iridaceae

Origin: South Africa

Clusters of re/brown bulbils on bulbil wastsonia stem.
It has clusters of up to 16 at nodes on the stem.

Regional Pest Management Plan (RPMP) status

  • Not a legally declared pest

View more about the RPMP statuses

General description

Perennial, clump-forming herb < 2 m tall. Corms are < 8 cm in diameter, stout and fibrous. Leaves are sword-shaped. Flowers are tubular, < 10 cm long, red/orange/pink/cream and borne on a spike in September-December. Cormils are shiny, red/brown and borne in clusters on floral stems.

What you need to know

Although bulbil watsonia is not a legally declared pest plant, it may still be invasive in some situations. Consider lower risk alternatives for your garden, such as native plants.

Habitats

Scrub, riparian margins, coastal dunes, wetland, wasteland, urban areas, roadsides.

Dispersal

Seed set is rare. Vegetative spread from corms and cormils, dispersed by water and soil movement. Human-mediated dispersal through dumping of garden waste and movement of contaminated soil, machinery and vehicles.

Impact on environment

Forms dense mats of corms, suppressing native seedling recruitment.

Control

Site Management

Follow up treated areas 3 times per year. Encourage natural regeneration of native plants or replant treated areas where possible after 2-3 treatments to establish dense ground cover and minimise reinvasion.

Recommended approaches

Physical control

Method: Dig out.

Plant parts requiring disposal: Underground corms and aerial corms.

Disposal options: Rot corms in covered water barrel or remove to greenwaste or landfill if practical.

Biocontrol

Biocontrol is currently not available for this species.

Community agrichemical control recommendations

No qualifications: Foliar spray with 150ml glyphosate green per 10L of water.

Basic Growsafe certified: Foliar spray with 3g metsulfuron-methyl plus 150ml glyphosate per 10L of water.

Certified Handler/Experienced agrichemical user: Foliar spray with 3g metsulfuron-methyl plus 150ml glyphosate per 10L of water and 10ml penetrant.

Caution: When using any herbicide or pesticide please read the label thoroughly to ensure that all instructions and safety requirements are followed.

A stalk of bulbil watsonia flowers in the forefront with the bushes towards the back.
It forms dense stands crowding out native species.
Photo credit: Holly Cox
A cluster of bulbil watsonia with dense scrub and tall stalks of flowers towering over the bush.
It has long stems with distinctive shiny red/brown clusters of bulbils. Each bulbil can produce a new plant.
Photo credit: Holly Cox
A hand holding a stalk of spiny bulbil watsonia flowers.
Bulbil watsonia tolerates high to low temperatures.
Photo credit: John M. Randall, The Nature Conservancy Wildland Invasive Species Team
A photo showing the pink flowers of Bulbil Watsonia.
Bulbil Watsonia may be invasive in some situations.
Photo credit: Trevor James - https://www.weedbusters.org.nz/