Answer: Here is a list of some flowering perennials that thrive in moist soil: 'Ice Ballet' Asclepsias, Chelone lyonii (Turtlehead Flower), Eupatorium (Joe Pye Flower), Filipendula (Queen of the Meadow), Marshalla grandiflora (Barbara's Buttons), Lobelia 'Ruby Slippers', Darmera peltata (Syn. Peltiphyllum peltatum - "Umbrella Flower"), Trollius chinensis (Golden Queen Globeflower), Ligularia przewalskii. An ornamental grass that does well in wet areas is Acorus, and, a good ground cover for wet spots is Tovara virginiana 'Painter's Palette'. Annuals such as Impatiens, Coleus, Primrose, and Snapdragon should do OK in that spot as well.
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