The radican sword is a large sword plant with broad, heart-shaped leaves on long stalks. It is closely related to the Amazon sword, but its leaves are rounder, and it is famous for sending leaves out of the water if given the chance.
Echinodorus cordifolius makes a bold centrepiece in a large tank. Its 'Marble Queen' and 'Tropica Marble Queen' varieties have leaves marbled with cream.
Origin
The species grows in marshes, ditches and the edges of ponds from the southern United States to Mexico and parts of South America. It spends much of the year growing emersed.
Appearance and growth
Submerged leaves reach 20–40 cm in tanks. Under strong light, the plant soon sends up long-stalked leaves that break the surface, and then flower spikes with white flowers.
Placement
Plant it as a solitary background or centre plant in a tank of at least 150 litres. It also suits open-top tanks and ponds, where the emersed leaves can be enjoyed.
Light, CO2 and nutrients
Low to medium light keeps it submerged. Strong light encourages emersed leaves. It is a heavy root feeder, so use a rich substrate and root tabs. CO2 is optional.
Water conditions
- Temperature: 20–28°C
- pH: 6.5–7.5
- Hardness: 3–15 dGH
Propagation and maintenance
Cut off any leaves that head for the surface as soon as they appear, to keep the plant compact and underwater. It produces plantlets on its flower stalks; pin these to the substrate until they root.
Compatibility
It suits most community tanks and many cichlid tanks, as its leaves are tough. Large plant-eaters may still nibble.
Common problems
Constant emersed growth, yellow leaves from a lack of root nutrients, and shading of smaller plants are the main issues.
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