Pistia stratiotes (Water Lettuce / Watersla)

Pistia stratiotes (Water Lettuce) is a large, free-floating tropical aquatic with rosettes of soft, velvety pale grey-green ribbed leaves and hanging feathery roots that absorb nutrients and provide hiding places for fish fry. Widely sold in Dutch and Belgian pond shops as a summer seasonal plant for nutrient export and surface coverage. It multiplies rapidly via stolons under good conditions. Must be kept indoors above 15°C in winter as it is frost-sensitive.

Float on pond surface in full sun. Water temperature minimum 20°C for active growth; bring indoors above 15°C in autumn. Excellent nitrogen absorber — ideal for new or heavily stocked ponds. Trim regularly to prevent total surface coverage which would reduce light to submerged plants. Not frost-hardy; discard or overwinter indoors.