Nymphaea nouchali aka Red And Blue Water Lily

Nymphaea nouchali is a water lily. It belongs to the family Nymphaeaceae. Common names include blue waterlily and blue lotus of India. It is native to the Old World's tropical and subtropical zones. Its range reaches the north of Australia. Useful Tropical Plants lists its range from Africa through Asia and Indonesia. It also lists the Philippines and New Guinea. The plant grows in rivers, lakes, pools, and wet ditches.

This soft-stemmed plant lives for more than two years. It grows from a thick, tuberous rootstock under water. Its roots hold it at the bottom of ponds and lakes. The leaves form a ring, or rosette, and float on top. Thus, some parts float, while others stay below the water. The flowers open by day and have a sweet scent. Insects bring pollen to the blooms. Gardeners grow this water lily for its looks in water gardens. People also gather wild plants for food and use in folk medicine.

The plant suits warm sites in tropical and subtropical zones. Kew puts it in the wet tropical climate group. In gardens, it prefers sun and a shallow pond. It needs standing water as part of its care. Growers can use seeds or split the rootstock to raise plants. Keep seeds moist until it is time to sow them. Sow them with their pulp in pots under shallow water. Move young plants to their own pots once floating leaves appear. Raise the water level as the plants grow. Each piece of split rootstock needs an eye that has begun to sprout.

Records list food uses for several parts, but there are safety concerns. People boil the seeds or grind them to make flour. They blend this with wheat and barley flour to make bread. People also eat the flowers, leaves, and flower stalks as vegetables. Records list the starchy tubers as food when cooked. Dried tubers can yield flour for use in porridge. The evidence also notes their use as food in times of famine. Some reports list raw use of the root. Yet the source warns that the root is poisonous unless cooked.

The plant has a long history of use in folk medicine. Its tissues hold compounds studied for their effects on living things. These include alkaloids and flavonoids. The flowers hold a high share of the flavonoids. The rhizomes also yield tannins. These uses do not prove that the plant is safe to eat. All parts but the seeds contain an alkaloid called nymphaeine. The source says it poisons frogs and causes tetanus-like signs. This warning does not show what effects it has on household pets.