Fragrant Waterlily

Nymphaea odorata

WA C Nymphaeaceae
Data Maturity Baseline

Washington State Classification

Class C — Widespread, County-Selected Control

Unmanaged fragrant water lily can form dense stands in water that can cover hundreds of acres and can persist until senescence in the fall.

Quick Reference

Type
aquatic emergent
Origin
Eastern half of North America, including southern Canada.

Identification

Growth Habit

It is an aquatic, bottom-rooted perennial. It has long, branched stolons extending up to 3.25 feet or more and lie just beneath the water’s surface. The nodes on the stolons typically produce a plant and many thread-like roots.

Leaves

Leaf blades are rounded to nearly circular with a slit in one side, have smooth margins, are green above and usually reddish or purplish or sometimes green below. Leaf stalks (petioles) are green or purplish and slender, sometimes faintly striped.

Flowers

Flowers are fragrant, floating and solitary, 2.4 to 7.5 inches in diameter, are on long stems and open in the morning and close in the evening. They have 17 to 43 white, though sometimes pink, petals and 4 sepals. Stamens number 35 to 120 and are yellow.

Fruit & Seeds

It forms leathery, berry-like capsules that contain many small seeds.

Impact

Unmanaged fragrant water lily can form dense stands in water that can cover hundreds of acres and can persist until senescence in the fall. It can restrict lake-front access, eliminate swimming opportunities, and outcompete native aquatic vegetation.

Ecology & Spread

Habitat

It grows rooted in mucky or silty sediments in water up to six to seven feet deep. It prefers quiet waters such as ponds, lake margins, and slow streams and will grow in acid or alkaline waters. Please click here to see a county level distribution map of fragrant water lily in Washington.

Spread Mechanisms

seed vegetative fragments water

Reproduction

The fragrant water lily reproduces through both seeds and spreading rhizomes.

Regional Notes — Puget Sound

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Control Methods

Mechanical

  • Continually removing all leaves as they emerge may kill plants after a few seasons. Cut plant material must be removed from waterways. Cutting must be done several times per year.

Biological Control

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