The term “lily pad” is a common name used to describe the large, floating leaves of several species of aquatic plants, leading to natural confusion about the blossoms they produce. These striking flowers do not have a single, separate common name; rather, they are simply named after the specific plant species that grows them. To understand what these flowers are called, one must first identify the two distinct types of plants that are most frequently mistaken for one another.
The Plants Behind the “Lily Pad”
The vast majority of plants whose leaves are called “lily pads” belong to one of two families: the Water Lilies (Nymphaeaceae) or the Lotuses (Nelumbonaceae). The flowers they produce are called Water Lily flowers or Lotus flowers. While the leaves look superficially similar, these two plant groups are only distantly related, belonging to different orders of flowering plants. The Water Lily family (Nymphaeaceae) includes the genus Nymphaea, which accounts for most of the floating flora seen in temperate and tropical ponds. Lotus plants, belonging to the genus Nelumbo, are distinct and characterized by their highly elevated blooms and leaves. The flower’s name is directly linked to its genus.
Anatomy of the Aquatic Blooms
The structure of aquatic plants is adapted for life rooted in the muddy bottom of a pond or lake, with leaves and flowers reaching the sunlight at the surface. A “lily pad” is the plant’s leaf blade (lamina), which is connected to the submerged stem (rhizome) by a long, flexible stalk called a petiole. These petioles contain hollow air canals (lacunae), which allow oxygen to diffuse from the leaf down to the rhizome and roots below the water.
Water Lily Characteristics
In Water Lilies, the leaf blade is typically rounded but features a distinct radial notch or slit extending from the edge to the center. The leaves and flowers of hardy water lilies usually float directly upon the water’s surface. Water Lily flowers are cup- or star-shaped, with numerous petals spiraling outward. They often sink back into the water after their brief blooming period to ripen their seeds.
Lotus Characteristics
Lotus plants have both their leaves and flowers rising high above the water on stiff, straight stalks. The leaves are perfectly circular and boast an exceptional waxy, hydrophobic surface, which repels water so that droplets bead up and roll off, a phenomenon known as the “Lotus effect.” The large, rounded Lotus flowers sit atop these stalks, sometimes reaching heights of four to six feet above the water line.
Water Lilies and Lotuses: Key Differences
The most immediate distinction between the two plants is the positioning of their foliage and flowers. Water Lily leaves are flat on the water and possess the characteristic V-shaped slit, while Lotus leaves are emergent, meaning they stand above the water.
Beyond their height, the reproductive structures provide a clear separation. Water Lilies ripen their seeds underwater in a berry-like capsule that sinks after the flower closes. Lotuses, on the other hand, produce a highly recognizable, shower-head-like seed head that remains elevated above the water, releasing its nut-like seeds from small holes once mature. Lotus flowers are also generally larger than Water Lily flowers, with some reaching up to a foot in diameter.