Water Lilies

Botanical name: Nymphaea spp.
Common name: Water lilies
Family name: Nymphaeaceae (Water Lily Family)
Native range: Cosmopolitan (except in very cold regions)
Location in Duke Gardens: Historic Gardens, Doris Duke Center Gardens
USDA Hardiness Zones: Varies by species

Aquatic plants have fascinated and delighted humanity for thousands of years thanks to their ability to bridge the gap between land, water and sky.  Think of water lilies (Nymphaea spp.), whose leaves and flowers directly float on the surface, and the powerful symbolism of the blue “lotus” in ancient Egypt and the sublime Impressionist paintings of Claude Monet likely come to mind. Unlike many plant genera, which are limited to particular locations or continents, water lilies are cosmopolitan in distribution except for very cold regions, with 65 species in all. Wherever you are on earth, you can probably find one suited to your region, climate and circumstances.

While this incredible diversity can make it hard to generalize their characteristics, one thing that all water lilies have in common is their distinctive leaves, which are round with a notch where the stem attaches. These leaves are filled with hollow air cells, which give them buoyancy and allow them to rise from the roots all the way to the surface. The same is true for the flowers, which open during the day and close at night, with each bloom lasting only a few days at most.

Although they are not true lilies (family Liliaceae), water lilies belong to an ancient lineage of plants—so old they predate birds, mammals and many species of flying insects. As a result, they are pollinated by beetles, similarly ancient creatures that favor wide, flat flowers that are easy to get in and out of. This is why water lilies have lots of stamens to dust beetle shells thoroughly with pollen, and why so many wild water lilies are white or greenish, though hybrids and cultivars come in a wide range of colors. Horticulturally, however, most water lilies are propagated asexually by tubers, and many garden hybrids and cultivars are completely sterile, though you’ll still find many insects—especially mosquito-hunting dragonflies—hanging around nearby.

Here at Duke Gardens, seasonal water lily displays are a regular occurrence in the Virtue Peace Pond and the koi pond in the Terrace Gardens. These aquatic plants are grown in pots placed on the bottom of the ponds rather than directly in the ground because these ponds are lined with stone and hardscape rather than soil. It also makes it easier to move the plants if necessary, especially tropical species that are sensitive to cold. Visitors in the fall might witness staff and volunteers tending to or removing water lilies, a complex operation that involves waders, boots and a lot of teamwork! The pots are then kept safely in the greenhouse over the winter. Any plants that remain outdoors will die back and go dormant in colder months, protected from the brunt of the chill by an insulating blanket of water.