Echinodorus uruguayensis

Echinodorus uruguayensis originates from the temperate rivers and marshes of Uruguay and northern Argentina, where it experiences seasonal temperature fluctuations well below those of its tropical cousins. In the aquarium it develops a large rosette of elongated, dark-green leaves with attractively ruffled or undulating margins, reaching 30–50 cm under good conditions. It is one of the most cold-tolerant sword plants available, thriving at temperatures as low as 18°C.

This cold tolerance makes it invaluable for subtropical setups housing fish such as Buenos Aires tetras, goldfish varieties, or temperate South American fish, where tropical swords would deteriorate. Despite its robustness in cool water, it grows equally well at tropical temperatures, making it a versatile background plant across a variety of aquarium types.

Like all larger Echinodorus, E. uruguayensis is a heavy root feeder and performs best in nutrient-rich substrate or with regular root tab supplementation. Its dark, ruffled foliage creates an impressive textural contrast against lighter-coloured plants.

Light: Medium (30–55 PAR); tolerates low light with reduced vigour. CO2: Not required; optional supplementation accelerates growth. Fertilisation: Root tabs every 3 months; liquid fertiliser with iron and trace elements weekly. Placement: Background specimen; plant singly or in small groups of 2–3 spaced 15 cm apart. Propagation: Adventitious plantlets develop on flower stalks — sever once roots are visible.