Watercress is a cool weather crop, so in warmer areas, it would do best to sow in autumn for a winter salad crop1.
Pinetree recommends starting these indoors in small pots, barely cover and keep moist for first month. Margaret Roberts recommends shading the bed with hessian, and never allowing it to dry out1. Once the seeds are at the 4-leaf stage, the hessian can be removed, but continue to kepp the seeds moist1.
Try to aim for a seed spacing of at least 2.34 inches (6.0 cm) and sow at a depth of around 0.0 inches (0.0 cm).Pick out the outer leaves for salads, or the side-shoot rosettes of leaves1.
These estimates for how long Watercress takes to sprout, grow and harvest are from real observations from real gardeners, right around the world.
Average 6 days | Min 4 days | Max 15 days (13)
Average days | Min days | Max days (0)
Average 50 days | Min days | Max days (0)
1 :Growing Herbs with Margaret Roberts; First published 1985