General: Water Lily Family (Nymphaeaceae). Yellow pond-lily is an aquatic perennial that grows to be 15 to 60 cm in height and spreads 1 to 2 m on the water surface. Spongy rhizomes anchor into the muddy bottom of a water body and give rise to long, stout stems.
Submerged leaves are thin and attached to the rhizomes. Floating leaves are thick, somewhat heart-shaped, wavy along the margins, have up to a 40 cm spread, and are attached to the stems. Flowers emerge on separate stem stalks. They are cup-shaped, yellow-green, with small scale-like petals and numerous stamens and stigmas hidden within the thick showy sepals. Flowers bloom from May to October, partially opening in the morning and closing at night. Spent flowers give way to seed heads that burst upon ripening, broadcasting their seeds over the water surface. Flowers and leaf stems die back to the rhizome in autumn.
Yellow pond-lily may be confused with water lily, Nymphaea species, which have rounder leaves and showier pink to white flowers.
Distribution: Yellow pond-lily is native to the Eastern United States, Africa, Temperate Asia, the West Indies, and Europe. It is naturalized in most temperate regions of North America. It occurs in all 50 states except Hawaii.
The USDA hardiness zones for yellow pond-lily are 4 to 10. It grows in wet, poor sandy soils and performs best in 1 to 3 feet of water in full sun to part shade. It is more tolerant of shade and deep water than Nymphaea species. It is more often used in large water gardens and ponds where it can produce underwater stems that grow up to 2 m long and can slowly spread to form sizeable colonies.
Yellow pond-lily should be grown in containers if they are used for water gardens. For natural ponds, plant rhizomes directly in the muddy bottom if naturalization is desired.
Seeds and Plant Production
Seeds are produced and deposited on the water surface, where they are carried to a germination spot. Yellow pond-lily reproduces more readily by spreading rhizomes.
Although this plant is not considered invasive, it is very difficult to eradicate when not grown in containers because any section of rhizome left behind may sprout new growth.
Brandy-bottle, bullhead lily, Nuphar variegatum, spatterdock, yellow cowlily.
Nuphar lutea is divided into many subspecies. Comparisons of morphological features and interpretations of molecular analysis indicate the name Nuphar lutea should not be used for any North American Nuphar members. The genus Nuphar is now represented by eight distinct species in North America. A key to this new classification is provided in Flora of North America, volume 3, by Kartesz (1997) and Aquatic and Wetland Plants of Northeastern North America, volume 1, by Crow and Hellquist (2000).
Ethnobotanic: Native Americans consumed the starchy rootstocks as boiled or roasted vegetables and harvested the seed for grinding into flour. There are some accounts of the root being powdered and used as a poultice.
Wildlife: Yellow pond-lily provides food and shelter for many fish and underwater insects.
Ornamental: Yellow pond-lily flowers and leaves are showy and fragrant. For this reason, it is used as an ornamental planting in water gardens and ponds.
Yellow pond-lily is a noxious aquatic weed in Puerto Rico.
This plant may become weedy in some regions or habitats and may displace desirable vegetation if not properly managed. Please consult with your local NRCS Field Office, Cooperative Extension Service office, or state natural resource or agriculture department regarding its status and use.