Medicinal and culinary herb Rich in vitamin A, C, and D it has a spicy taste the leaves are added to salads. Can be cultivated in the garden or in pots or punnets indoors all year round, must be kept very moist, pots or punnets can be stood in water, the water being changed daily. Outdoors broadcast sow spring when ground has warmed up onto shady moist soil, keep moist. Watercress is an excellent addition to mixed salad leaf for the salad bowl. Harvest at any stage from micro or baby leaf to mature leaf from June through to winter if crop is protected. Popular Micro Greens. Hardy perennial Culinary herb, Oriental veg. Nasturtium officinale.