General description

Perennial water lily. Stolons are long and float near surface. Leaves are floating, heart-shaped and < 10 cm in diameter. Flowers are yellow with fringed petal and corolla margins, < 3.5 cm in diameter and borne on long stalks above the water’s surface in November – April.

What you need to know

To help protect our environment:

  • You must not breed, distribute, release or sell marshwort. As marshwort is a National Pest Plant Accord species, these restrictions apply within the Auckland region and across the whole of New Zealand.
  • You must not plant marshwort within the Auckland region.
Auckland Council will control marshwort at all sites where it is known to occur.

If you see marshwort anywhere in the Auckland region, please report it to Auckland Council at

Still or slow-moving freshwater bodies.

Vegetative spread from stem and leaf fragments. Human-mediated dispersal through deliberate plantings.

Forms thick mats, smothering vegetation, impeding drainage, and interfering with recreational activities. Potential to impact on the mauri of wai māori.

Site Management

Recommended approaches

Do not attempt to undertake control of this species. Please report to Auckland Council.

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

Similar species

fringed water lily
Nymphoides peltata

Fringed water lily has leaves with scalloped margins.

water poppy
Hydrocleys nymphoides

Water poppy has an oval leaf with an inflated mid vein on the underside.

yellow water lily
Nuphar lutea

Yellow water lily has larger leaves and spongy stolons.

Mexican water lily
Nymphaea mexicana

Mexican water lily has a larger leaf with a definite main vein.

Search tags

RPMP status

Whole region (Eradication)
National Pest Plant Accord Species
Marshwort - Main species image