Encyclopedia - Plants for ponds
Watercress
Nasturtium (Rorippa)
Family Brassicaceae Burnett (Cruciferae Juss.), genus Rorippa Scop.
Common watercress, or medicinal watercress, or watercress (lat. Nastúrtium officinále = Rorippa nasturtium-aquaticum) — a fast-growing perennial aquatic or semi-aquatic plant of the Cabbage family, distributed from Europe to Central Asia. It has been used since ancient times as a leafy vegetable.
Stems are creeping, thick, hollow, up to 50—60 cm long. Leaves are green, pinnately divided, with broad petioles and 2—7 pairs of oblong or oval leaflets and a larger, rounded-ovoid terminal leaflet. The plant flowers with small white flowers gathered in semi-umbels. Calyx segments are equal, reflexed. Petals have claws, are oblong-obovate, white. The short stamens have one large horseshoe-shaped nectary gland open to the outside; there are no median glands.
After flowering it produces a fruit — a short, inflated pod with convex valves, without veins, containing oblong, flat seeds. Seeds are arranged in each cell in two rows. Flowers from May to August.
Common watercress grows wild in moist places (ponds, springs, ditches, etc.). In the garden it is grown from seeds or cuttings. It prefers shaded places. Early in spring it can be planted first in a cold frame, then after two weeks into open ground. Irrigation furrows are made between the beds. The plant is cut frequently until flowering shoots appear. It can also be used then, but the taste will be very bitter.
Location: grows better in direct sunlight. Not demanding to soil. Plant directly in the ground on a marshy bank or in containers that can be sunk to about 15 cm.
Care: remove excess plants when they spread. Winter-hardy.
Propagation: by cuttings and seeds.