Echinodorus osiris

Echinodorus osiris, the Red Melon or Melon Sword, is a popular Brazilian species prized for its dramatic leaf colouration. New leaves emerge from the centre of the rosette in a vivid reddish-bronze to copper colour, which gradually transitions to deep olive-green as they mature and expand. This two-tone effect — red new growth surrounded by dark mature leaves — creates a living colour display that changes continuously as the plant grows.

It forms a substantial rosette reaching 30–50 cm tall in well-fertilised conditions, making it a true background plant for medium and large aquariums. The leaves are oval with a broad, rounded tip and clearly defined venation, giving the plant a refined appearance compared to the narrower Amazon Sword. It is a moderately easy species that thrives in the same range of tropical conditions as most other Echinodorus.

The Red Melon Sword is particularly effective in South American biotope aquariums and planted community tanks where warm colours are desired to complement the fish palette. Its red growth complements species such as red-finned tetras and cardinal tetras beautifully.

Light: Medium (35–65 PAR); brighter light enhances the red coloration of new leaves. CO2: Not required; CO2 supplementation deepens and prolongs the red of emerging leaves. Fertilisation: Root tabs every 3 months; liquid fertiliser with iron weekly to maintain vivid leaf colour. Placement: Background or midground; plant singly as a specimen; keep crown above substrate. Propagation: Flower stalks produce daughter plantlets — remove once 4+ leaves and roots have developed.