A rain garden is a shallow basin designed to slow, capture, and temporarily hold stormwater runoff for a day or two. This duration prevents mosquito breeding while allowing water to percolate into the soil, reducing flooding and supporting groundwater recharge.

What Are the Key Components and Zones of a Rain Garden?

A rain garden consists of a shallow basin for temporary ponding (a few inches deep) and a supporting plant community. It is structured into distinct zones based on water depth:

• Center of the Basin: Holds water the longest; best suited for deep-rooted plants that tolerate temporary wet conditions (“wet feet”).
• Shallow Margins: Ideal for moisture-loving plants that prefer shorter periods of wetness.
• Berm: The raised outer ridge; best for plants that prefer drier conditions.

What Native Plants Work Best in a Rain Garden?

Native plants are ideal because their deep roots increase resilience during dry periods. (Note: Watering is required while plants become established).

• Perennials: Louisiana iris, swamp milkweed, blue mistflower, bee balm, swamp sunflower, Joe-Pye weed, Texas star hibiscus, Texas spider lily, giant coneflower, cardinal flower, and ironweed.
• Shrubs: Buttonbush, southern wax myrtle, and dwarf palmetto.
• Trees: Bald cypress, river birch, and paw paw.
• Grasses: Brushy bluestem, inland sea oats, and seep muhly.

What is a Bioswale and How Does It Differ From a Rain Garden?

A bioswale is a plant-filled shallow ditch that carries runoff water toward a rain garden. While planted with moisture-tolerant plants, a bioswale routes water rather than collecting and holding it like a rain garden does.

How Should You Position a Rain Garden Near Structures?

When capturing water from roof downspouts and gutters, use a bioswale to lead water to a rain garden located at least ten feet away from the structure’s foundation to prevent water damage.