Potamogeton amplifolius, commonly known as Largeleaf Pondweed or Broad-leaved Pondweed, is a perennial aquatic plant native to lakes, ponds, slow-moving rivers, and protected bays in North America. It is particularly adapted to clear, nutrient-rich waters and can be found at varying depths, often in deeper water than many other pondweeds. This species can reach lengths of up to a meter with very slender, cylindrical stems. The leaves are variable, with submersed leaves being up to 8 inches long and 7 inches wide, while the floating leaves are smaller, reaching up to 4 inches long and 5 inches wide. The inflorescence consists of a spike of many small flowers that emerge above the water surface on a robust peduncle, typically blooming in the summer months.

Largeleaf Pondweed is valued for its role in aquatic ecosystems, providing habitat and food for aquatic wildlife. It can be used in water gardens and naturalized ponds, contributing to the oxygenation and stabilization of the aquatic environment. In cultivation, it requires full sun to part shade and grows best in calm, nutrient-rich waters with a neutral to alkaline pH. While generally low-maintenance, it can become invasive in ideal conditions, potentially outcompeting native species. Care should be taken to manage its growth in smaller water bodies to prevent it from becoming problematic.CC BY-SA 4.0