Overview
Nasturtium officinale is a semi-aquatic perennial reaching 4-12 inches (10-30 cm) tall with a spread of 12-24 inches (30-60 cm) and a trailing, creeping habit that roots at nodes along floating or creeping stems. Native to Europe and western Asia, it grows in or alongside running water—streams, springs, and shallow channels—and is one of the oldest known leafy greens consumed by humans. Small, round to ovate, dark green, pinnately compound leaves on hollow stems with a sharp, peppery, mustardy flavor (Brassicaceae family). Stems are succulent and break cleanly. Days to first harvest 50-60 from seed, or continuous from established plantings. Growth rate is fast in cool, flowing water. Hardy to zone 3. Requires consistent moisture—will not tolerate dry soil. Can be grown in containers with standing water.
Native Range
Nasturtium officinale is native to Europe and western Asia. Naturalized throughout temperate regions worldwide including North America, where it grows in streams, springs, and wet habitats.Suggested Uses
Grown in water gardens, containers with standing water, or streamside for culinary use—salads, sandwiches, soups, garnish, juicing. Sharp peppery flavor. One of the oldest leafy greens. Semi-aquatic. Continuous harvest. Hardy perennial z3. Rich in vitamins C and K. Requires constant moisture or standing water. Wild-harvested watercress may harbor parasites—use cultivated sources.How to Identify
Appearance
Size & Dimensions
Height4" - 1'
Width/Spread1' - 2'
Bloom Information
Small white, four-petaled flowers in terminal clusters from late spring through summer. Flowers indicate bolting—flavor becomes more pungent. Harvest before flowering for mildest flavor. Self-seeds freely in wet habitats.Detailed Descriptions
Flower Description
White; small four-petaled; terminal clusters; late spring-summerFoliage Description
Dark green; small pinnately compound; on hollow succulent stemsGrowing Conditions
Sun Requirements
Requires 3-6 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Sow seed on the surface of wet soil or in shallow trays of water—do not cover (needs light to germinate). Keep constantly wet. Grows in containers with 2-3 inches (5-8 cm) of standing water, refreshed regularly. Cool temperatures 50-65°F (10-18°C). Part shade in summer to delay bolting. Harvest by cutting stems 2 inches (5 cm) above water line. Regrows quickly. If growing in natural streams, ensure water source is clean—watercress can harbor parasites in contaminated water.Pruning
Cut stems 2 inches (5 cm) above waterline or soil. Regrows within 1-2 weeks. Harvest before flowering for best flavor.Maintenance Level
moderateContainer Growing
✓ Suitable for container growing
Minimum container size: 2 gallons