Echinodorus horizontalis

Echinodorus horizontalis is native to the rivers and seasonally flooded forests of Peru and Colombia in the western Amazon basin, where it grows in soft, slightly acidic water with moderate light filtering through the forest canopy. Its most distinctive feature is the orientation of its leaves: broad, heart-shaped blades are held nearly horizontally on spreading petioles, creating a wide, flat rosette that can occupy a large footprint relative to its height of 20–40 cm.

This horizontal growth habit means the plant requires considerable lateral space in the aquarium — it suits mid-to-large tanks where its spreading form can be appreciated without crowding. The leaves are a rich green with clearly visible lateral veins, and the overall appearance is bold and sculptural. It is slower to produce new leaves than the common Amazon Sword but is no more demanding in its water chemistry or lighting requirements.

E. horizontalis is a rewarding choice for aquascapers seeking to break the vertical monotony typical of sword-plant layouts, offering a genuinely different geometric profile as a midground specimen.

Light: Medium (35–60 PAR); tolerates moderate shade but benefits from good illumination. CO2: Not required; CO2 supplementation improves leaf size and colour. Fertilisation: Root tabs every 3 months; liquid fertiliser weekly with balanced NPK and iron. Placement: Midground; allow at least 25–30 cm lateral clearance to accommodate spreading petioles. Propagation: Produces daughter plants on flower stalks — sever once self-rooted.