Watercress
Nasturtium officinale
Watercress is a fast-growing aquatic perennial with peppery, rounded leaves, eaten in salads, sandwiches and soups. It can be grown in a container of constantly wet soil or slowly flowing water.
Photo: Masparasol · CC BY 3.0, via Wikimedia Commons
Essential Care Requirements
Light
Partial sun, Full sun
Watering
High
Keep the soil saturated; stand pots in a tray of water changed daily.
Soil
Rich, wet potting mix; pH 6.5–7.5.
Temperature and humidity
0–25 °C · High humidity
Feeding
Feed lightly with a liquid fertilizer every few weeks.
Pruning and propagation
Propagate by stem cuttings, seed
Cut stems often to keep it bushy; remove flowers.
Home-grown watercress is safe. Wild watercress from streams near livestock can carry liver fluke and should not be eaten raw.
Top Cultivation Tips
Shop-bought stems root in water within days.
Change the water daily to keep it fresh.
Grows best in cool weather.
Harvest before it flowers.
Common problems
Aphids
Small, soft-bodied insects that cluster on new shoots and buds, sucking sap and leaving sticky honeydew behind.
How to treat it →PestCaterpillars
The larvae of moths and butterflies, which chew holes in leaves, flowers and fruit and can strip a plant in days.
How to treat it →PestFlea beetles
Tiny, shiny jumping beetles that pepper the leaves of brassicas, radishes and aubergines with small holes.
How to treat it →
