Cardamine lyrata Japanese Cress

Cardamine lyrata is native to East Asia, growing naturally in cool, shaded streams and rice paddies in Japan, Korea, and China. In the aquarium it is valued for its unusual leaf shape — broadly lobed, with a texture reminiscent of watercress — and its preference for cooler water temperatures that make it suitable for unheated tanks. Under warmer conditions the plant can transition to emersed growth, producing small white flowers. It is easy to grow and provides a distinctly different leaf texture from typical aquarium plants.

Light: Low to medium (15–40 PAR); adapts well to low light conditions. CO2: Not required; grows without supplementation in cool, well-oxygenated water. Fertiliser: Light weekly balanced fertiliser; low nutrient demands compared to most stem plants. Planting: Midground groups of 3–5 stems spaced 3 cm; trim every 3–4 weeks. Growth: Moderate; 15–30 cm; cool water (18–24°C) is key for sustained submerged growth.