Nymphaea mexicana

Nymphaea mexicana is a subtropical to tropical species native from Mexico through the southern United States, growing in warm, shallow lakes, ponds, and slow-moving waterways. The floating pads are attractively marked with green and purplish-brown mottling, and the bright canary-yellow flowers are held just above the water surface, opening during daylight hours with a faint sweet scent. It is one of the more vigorous yellow water lily species and can colonise aggressively in warm, nutrient-rich conditions.

This species is a parent of many popular yellow-flowered hardy water lily cultivars and carries their characteristic vigour. It is suitable for heated ponds and large water features in warm temperate to tropical climates. In cooler regions it should be treated as a tender perennial, brought indoors before frosts or stored dormant.

Nymphaea mexicana adapts well to a range of water depths from 20–80 cm and performs best in full-sun positions. It is less demanding of water quality than many tropical lilies and will grow in moderately hard, alkaline conditions.

Light: High (full or near-full sun for best flowering performance). CO2: Not required under natural conditions. Fertilisation: Aquatic fertiliser tablets in the growing medium every 6–8 weeks during growing season. Placement: Warm-water pond or tub at 20–80 cm depth; full sun position preferred. Propagation: Rhizome division in spring; also stoloniferous — produces side runners that form new plants.