Water LettuceText Box: WATER LETTUCE ( Pistia stratiotes ‘Rosette’) Pale green, shell shaped leaves that form a rosette shape. Needs warm water and warm weather to survive. Weather permitting Water Lettuce is shipped from April through July. Call for availability early and late in the season. We do our best to be aware of the plants not allowed to be shipped to your state, however, the responsibility is the buyers if your not sure check with your local USDA Office