May 27, 2025

Rain Gardens: Catch and Hold Runoff Water

Doesn’t it seem like we’re always wishing for rain or wishing it would stop? For sure, it’s no fun when it pools up next to the house, even in a brief cloudburst. And then we watch all that free water swoosh down the street, flooding the gutters, when our plants are gasping. Through rain gardens, though, we can keep some of that precious resource in our soil, and rain tanks let us store the windfall for a non-rainy day.

To illustrate how neighborhoods can work together in rain catchment designs, the City of Austin initiated the Rain Catcher Pilot Program to integrate and leverage existing Green Stormwater Infrastructure programs and resources.

In a collaboration with Urban Patchwork designer Paige Oliverio, they worked with gardeners, including Larry and Jessica Morse, to design rain tank systems and rain gardens with beautiful native and adapted plants for pollinators. On an autumnal-like December morning, we visited two of the front yard gardens.

Basically, a rain garden is simply a depression in the ground, generally 6-12” deep. Scooped-out soil and mulch form berms to contain the basin (swale). “When we remove some of this square footage of just the lawn, we are doing a lot to help revitalize the soil in that space. Healthy soil is going to hold a lot more water, instead of just running right off into the street. And what happens is we end up with a cooling effect in the summer,” Paige explains.

In Central Texas, rain patterns can mean 1 – 3” of rain all at once (like on Memorial Day weekend) and then no rain for weeks or even months. A rain garden basin absorbs and filters that rapid rainwater runoff. Rain garden plants don’t mind temporary flooding between dry times. Here’s a list of rain garden plants and designs—geared for schools, but helpful for everybody.

Although the pilot program is on hold for now, the concepts have been part of the city’s Grow Green and Green Stormwater initiative for many years.

Watch CTG’s 2017 interview about rainwater berm and swale designs with Jessica Wilson, Education Manager, Watershed Protection.

Gardening for birds and insects has always mattered to Jessica and Larry. “20 years ago or more, I actually put in a complete xeriscape with native plants in the front yard,” Jessica tells us. “And as we were having more difficulty with flooding, I heard about this program and I thought it would help me have water for all my native plants, and it would also help with rain mitigation, flood mitigation for me and for the neighborhood.”

They planted their rain garden in fall 2023, including deep-rooted grasses like Lindheimer muhly that help infiltrate water, and pollinator perennials like Engelmann daisy. I spotted bluebonnet and standing cypress seedings among the many perennials. Once established, these plants get by on little irrigation, but the 1000-gallon rain tank at the front porch gives them a boost when things are dry.

Paige meets with another owner, Graham Emmons, who planted his rain garden in spring 2024. Not even a year old, already plants are rapidly growing, including a new Monterrey oak through TreeFolks’ NeighborWoods.

Plants can be native or adapted. Graham’s rain garden contains esperanza (Tecoma stans), Mexican bush sage, ‘Henry Duelberg’ salvia, Mexican honeysuckle, anacacho orchid, Lindheimer muhly, sedges, herbs, a cenizo and that young Monterrey oak.

For Jessica and Larry, the garden’s simply fun to watch as the seasons and the wildlife change. Jessica tells us: “The grasses are blowing in the breeze, and we’re next to the street, and we have people come up and ask us about this unusual garden we have in our front yard.”

Thank you for stopping by! Linda

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