Installing a Rain Garden

Here in South Florida, it’s no secret that we receive a large amount of rain. The water that hits your roof generally just flows down the gutter and out through your grass. Large volumes of water often lead to soggy lawns, overworked sump pumps, and soil erosion. It can carry harmful pollutants gathered from roofs and fertilizers to our rivers and streams, since storm water runoff is not treated at a plant the way wastewater is. A simple and beautiful solution to all these problems is to install a rain garden!

Rain gardens are a natural way to filter pollutants from storm water before it reaches our waterways, as well as to slow its velocity to decrease the chance of erosion. They can be as small as a few square feet, or they can be a central feature in your landscape. Rain gardens feature beautiful native plants that have deep roots and help drain water. They double as habitat for pollinators like butterflies and bees, so you’re not only helping clean the water–you’re saving our pollinators as well! Do you want to install a rain garden of your own? Here’s how to do it.

1. Choose the site for your garden. You want this to be in a low-lying area of your yard at least 10’ away from your house, but one that still has good drainage. Luckily, most of our soil types here in Florida are well-draining.
2. Once you’ve located your site, use a can of spray paint to delineate its borders. Ovals or kidney bean shapes are the most popular for rain gardens. Besides the basin itself, you’ll need to create a channel of large stones or plastic that leads from your gutter to your rain garden, and plan for an overflow path to send excess water during large storm events.
3. Remove the sod and dig out the basin and channel. Cut the sod and pull it up in strips, or lay cardboard or mulch over the grass to kill it. After the grass is gone, dig a basin 18” deep, with a relatively flat bottom so that water infiltrates the ground evenly. Dig a channel about 10” wide and 8” deep that leads from your downspout to the garden, and fill with riprap or medium-sized river stones.
4. Fill it with 12” of rain garden soil (a 30-30-30 mix of sand, topsoil, and compost). Pile soil to create gradual slopes up to the edges of the basin. The result is a shallow depression in the basin.
5. Create your overflow. On the side of the garden that you determined your emergency overflow should go, dig a 2’ stretch of the edge of the bed about 4” lower than the surrounding rim. Lay river stones over this edge and continue out one or two feet from the rim into your yard to help prevent erosion and dissipate the excess water as it leaves the garden.
6. Add your plants! Plants that can tolerate having “wet feet” should be planted in the center of the rain garden, where it will remain wet the longest after a storm. Some good choices for South Florida include blue flag iris and swamp sunflower. Along the slopes, plant other beautiful natives such as goldenrod, spider lily, milkweed, muhly grass, and wiregrass. Don’t forget to add mulch once they’re all planted.

   Big Earth Landscape Supply is your one stop shop for all the gardening tools, soil, river rocks and other supplies you’ll need to install a beautiful rai n garden – or any other landscaping project you want to undertake! With 4 area locations in Sarasota and Tampa, we are never too far away.