Watercress

Watercress is an aquatic or semi-aquatic flowering plant in the mustard family, Brassicaceae, usually identified as *Nasturtium officinale*.

Watercress is an aquatic or semi-aquatic flowering plant in the mustard family, Brassicaceae, usually identified as *Nasturtium officinale*. Native to Eurasia, it is now cultivated and naturalized in many parts of the world. The plant is known for its peppery leaves and is widely eaten as a leafy green. In Canada, watercress is grown and sold as a culinary leafy green, and it is relevant to Canadian readers as both a food plant and a freshwater species that can become naturalized outside its native range.

Taxonomy

Watercress is generally treated as *Nasturtium officinale* in the family Brassicaceae, though older sources may use *Rorippa nasturtium-aquaticum*. It is related to other mustard-family vegetables such as cabbage, kale, and mustard greens.

Description

The plant is a fast-growing perennial herb with hollow stems, small round to oval leaves, and small white flowers. It can grow submerged, floating, or emerging from shallow water.

Distribution and habitat

Watercress is native to Eurasia but has become naturalized or introduced in many other regions, including North America, South America, Australia, South Africa, and New Zealand. It typically grows in springs, streams, and other clean freshwater habitats.

Uses

Watercress is valued as an edible green with a sharp, peppery taste and is used in salads, sandwiches, garnishes, and cooked dishes. It is also grown commercially in controlled aquatic beds.