Nasturtium

General description

Short-lived, hairless, scrambling herb. Stems are fleshy, < 10 m long and creeping or sprawling. Leaves are round, paler underneath and borne on a stalk attached to their undersides. Flowers have a basal spur and are tubular, orange/red/yellow and borne in October – May. Fruit is fleshy, green, segmented and contains ribbed green seeds.

What you need to know

Although nasturtium 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

Riparian margins, shrubland, wetlands, disturbed sites, urban areas, wasteland, roadsides.

Dispersal

Seeds dispersed by water and possibly birds. Vegetative spread from stem fragments. Human-mediated dispersal through dumping of garden waste.

Impact on environment

Can form dense infestations and smother vegetation.

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: Pull out.

Plant parts requiring disposal: Seeds.

Disposal options: 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 100ml glyphosate green per 10L of water.

Certified Handler/Experienced agrichemical user: Foliar spray with 100ml glyphosate green per 10L of water and 20ml penetrant.