Nymphaea gigantea Hook.

A water lily. A plant which grows in water. It grows 8-40 cm high and spreads 0.9-3.5 m wide. It is a herb with a round rhizome or underground stem. The leaves are 80 cm across. They are round but with a slit towards the centre. They float on the water. They are green. The edges have uneven teeth about 0.5 cm long. The flowers are about 25 cm across. They grow on stems which reach 50 cm above the water. There are 4 sepals and 32 petals. The sepals are 11 cm long and green with purple stripes. The petals are white, pink or blue. The flowers open during the day and close at night. The fruit is a berry 5 cm across. It is round.

It is a warm temperate, subtropical and tropical plant. It usually grows in pools or permanent water. It can grow in water 1-3 m deep. It grows in soft mud. It needs water above 27°C to bloom and grow. It suits hardiness zones 11-12.

Nymphaea gigantea features on a $2.30 Australian postage stamp issued 27 September 2017, one of a series of three Australian native aquatic plant stamps.

Plants can be grown from seed or by division of the rhizome.