Rain Garden Plants: Best Species for Wet Sites

Rain gardens are shallow, planted depressions designed to capture stormwater runoff, allowing it to infiltrate slowly while filtering pollutants. They mimic natural hydrology, reduce erosion, and create habitat. Success depends on selecting plants that tolerate both periodic flooding and dry spells.

Design Principles

• Locate at least 10 feet from foundations, in a natural low spot or where downspouts direct water.
• Size to handle runoff from impervious surfaces (roof, driveway).
• Amend soil with compost and sand for infiltration.
• Create three zones: bottom (wettest), slopes (moist), edges (driest).

Recommended Plants by Region

Choose native species adapted to local conditions. Below are examples for mid-Atlantic and southeastern U.S.; consult your extension service for regional lists.

Mid-Atlantic (DE, NJ, MD)

• Perennials: New England aster, blue flag iris, cardinal flower, swamp milkweed, white turtlehead, Joe-Pye weed, wild geranium, Virginia bluebells.
• Grasses/Sedges: Woolgrass, soft-stem bulrush, Canada rush, bottlebrush grass, inland sea oats.
• Ferns: Christmas fern, ebony spleenwort.
• Shrubs/Trees: Redbud, oakleaf hydrangea, sweet pepperbush, river birch.

Southeast (AL and similar)

• River birch, sweet pepperbush, oakleaf hydrangea, cardinal flower, indigo, redbud, turkey tangle fogfruit, dwarf palmetto, eastern gamagrass, desert false indigo.

Maintenance

Once established, rain gardens need minimal care: no supplemental watering, little fertilizing. Annual tasks: remove sediment/debris, cut back dead growth in late winter, divide overcrowded plants, monitor invasives. They attract pollinators and birds, enhancing biodiversity.