Nymphoides peltata (Yellow Floating Heart) is a vigorous aquatic perennial boasting floating, rounded, flat, emerald-green leaves, 4 in. across (10 cm). Resembling miniature water lily leaves, they create a lovely backdrop for the star-shaped bright yellow flowers, 1 in. across (2.5 cm), that arise on long stalks above the floating leaves. The edges of the petals are fringed. Blooming from late spring to early fall, this aquatic, bottom-rooted perennial plant can grow in dense mats and reproduce prolifically through both vegetative and sexual means. These dense mats have the potential to shade and crowd out native aquatic plants. Yellow Floating Heart is very difficult to control due to its ability to form a new plant from rhizomes, stolons, separated leaves, or seeds.

• Grows up to 3-6 in. tall (7-15 cm) and 12-36 in. wide (30-90 cm).
• Performs best in full sun in organically rich sandy loams or containers and submerged in 12-24 in. of water (30-60 cm).
• Suitable for ponds, and water gardens.
• No serious pest or disease issue. Keep an eye out for water-lily beetle, water lily aphid, brown china-mark moth, and false leaf-mining midge.
• Deadhead and remove yellow leaves regularly. 
• Propagate by runners removed in summer.
• Native to Europe, Asia.
• Nymphoides peltata is declared a noxious weed in New Zealand and parts of North America and is also declared invasive in Sweden. It is listed on Schedule 9 of The Wildlife (Northern Ireland) Order (1985) as amended and on Schedule 3 of the EU (Birds and Natural Habitats) Regulations 2011 in the Republic of Ireland as an invasive non-native species.
• Find where it is invasive in the U.S.