Potentilla sundaica, commonly known as Marsh Cinquefoil, is a semi-deciduous herbaceous perennial native to peat bogs, fens, wet meadows, and marshes across temperate regions of Asia. It typically grows to a height of 1-2.5 feet (0.3-0.8 meters) and spreads 1-1.5 feet (0.3-0.5 meters). The plant features pinnate leaves and distinctive deep purple to maroon flowers with five petals that bloom in the summer, providing a unique color contrast to the more common yellow flowers of other Potentilla species. The flowers are modestly showy and attract pollinators such as bees and butterflies.

Marsh Cinquefoil is valued for its tolerance of wet conditions and is often used in water gardens, bog gardens, and for naturalizing in damp areas. It is also utilized in ecological restoration projects to stabilize soil and provide habitat for wildlife. This plant thrives in full sun to part shade and prefers consistently moist to wet soils, including loam or clay with poor to medium drainage. While it is generally low-maintenance, it can spread by rhizomes, potentially becoming aggressive in ideal conditions. Gardeners should be aware of its spreading habit and manage it accordingly to prevent unwanted naturalization.CC BY-SA 4.0