Many plants will not grow well in soils that are constantly moist or wet. However, there are a number of plants that are tolerant of and have adapted to perform well under these conditions. Moist generally means soils that are constantly damp and wet refers to soils that are saturated with occasional exposure to standing water (1 day duration).
Hardy Hibiscus - Hibiscus sp.
Height: 2-4 feet.
Width: 2-5 feet.
Bloom: red, white, pink, Bicolor, July-Sept.
Cultivars: 'Fireball', 'Copper King', 'Luna' series, 'Lady Baltimore'.
Notes: Large impressive blooms. Slow to emerge in the spring. Performs best in moist soil in a sun to part shade location.
Queen of the Prairie - Filipendula rubra
Height: 18 inches - 6 feet.
Width: 3-4 feet.
Bloom: Pink, white, June-July.
Cultivars: 'Flore Plano', 'Aurea', 'Kahome'.
Notes: Clusters of frothy blooms. Good for rain gardens. Best in full sun to part shade.
Black Snakeroot - Cimicifuga racemosa
Height: 2-5 feet.
Width: 3-4 feet.
Bloom: White, Pink, Aug-Sept.
Cultivars: 'Pink Spike', 'White Pearl', 'Brunette'.
Notes: Large, dramatic plant. Late season flower display. Best in part to full shade.
Rocket Ligularia - Ligularia dentate
Height: 3-4 feet.
Width: 2-3 feet.
Bloom: Yellow, July- Aug.
Cultivars: 'Othello', 'The Rocket', 'Osiris Café Noir'.
Notes: Dramatic foliage, daisy-like flowers, late season flower display. Best in sun to part shade.
Cardinal Flower - Lobelia cardinalis
Height: 2-3 feet.
Width: 18-24 inches.
Bloom: Red, blue July-Sept.
Cultivars: 'Angel Song', 'Ruby Slippers', 'Arabella's Vision'.
Notes: Good accent plant. Needs moisture for best performance. Best in sun to part shade.
Meadow Rue - Thalictrum aquilegifolium
Height: 3-5 feet.
Width: 18-24 inches.
Bloom: Lavender, July-Aug.
Cultivars: 'Black Stocking', 'Hewitt's Double', 'Evening Star'.
Notes: Distinctive, lacy columbine-like foliage. Best in sun to part shade.
Spiderwort - Tradescantia x andersoniana
Height: 12-18 inches.
Width: 18-24 inches.
Bloom: White, blue, purple, June-July.
Cultivars: 'Snowcap', 'Sweet Kate', 'Concord Grape'.
Notes: Can be cut back to refresh plant appearance in midseason. Can spread.
Royal Fern - Osmunda regalis
Height: 4-6 feet.
Width: 3-4 feet.
Bloom: none.
Notes: Very large graceful fern. Good along shaded water features. Best in part to full shade.
Finger-leaf Rodger's Flower - Rodgersia aesculifolia
Height: 3-5 feet.
Width: 4-5 feet.
Bloom: White, July.
Notes: Very large leaf bold plant. Good along water feature. Best in part shade.
Leopard's Bane - Doronicum orientale
Height: 18-24 inches.
Width: 18-24 inches.
Bloom: Yellow, April-May.
Notes: Early flowering, daisy-like flowers. May go dormant during the summer. Best in sun to part shade.
Siberian Iris - Iris siberica
Height: 2-3 feet.
Width: 2-3 feet.
Bloom: Lavender, June.
Cultivars: 'Caesar's Brother' 'Little White'.
Notes: Very wet tolerant, fine grass-like foliage. Best in sun to part shade.