Watercress is a productive perennial in zones 6–9, grown for its tender, succulent leaves. Plants harvest well for several months before tapering, so a mid-season sowing can extend the supply.
Sow 1/4 inch deep in spring when soil reaches 60°F, then thin seedlings to 3–6 inches apart. Keep the soil moist throughout growth; in containers, immerse the established pot in a water-filled container and change the water often.
