AppearanceNymphoides peltata is an herbaceous, perennial, aquatic plant that has stout, branching stems up to 0.1 in. (2-3 mm) thick. It is often found rooted in the mud of still bodies of water.Foliage The leaves, which arise from rhizomes and are usually opposite and unequal. The leaves are cordate to subrotund in shape measuring from 2-6 in. (5-15 cm) long and wide.Flowers The bright yellow flowers of Nymphoides peltata have five petals, and measure from 1-1.5 in. (3-4 cm) in diameter when fully open. There is one to several flowers on each stalk. The edges of the petals are fringed. This plant flowers from June to September.Fruit The seeds of are contained in beaked capsules that measure 0.5-1 in. (1.2-2.5 cm) in length. The seeds themselves are flat and oval in shape, and have ciliate margins that measure 0.1 in. (3.5 mm) in length.Ecological Threat Although N. peltata has the potential to shade and crowd out native aquatic plants. In warmer areas it has formed large stands that can block waterways. N. peltata is still commonly sold as a plant for water gardens, and can be carelessly disposed of into local waterbodies. It prefers the still waters found in lakes and ponds. It is often found in water gardens, which are the source of many of its introductions.