Things To Know
Rain Garden

5 Steps for Creating a Rain Garden

Stormwater runoff is a major cause of water pollution in streams and rivers

Rain gardens are shallow depressions that are planted with deep-rooted native and non-native adaptive plants and grasses. They are:

  • Designed to collect rain water that runs off rooftops or lawns
  • Areas that capture stormwater runoff, allowing it to soak into the ground. This recharges groundwater and naturally filters out pollutants.
  • A source of food and habitat for birds and butterflies
  • Creating a rain garden not only shows your interest in protecting the environment, but also can be a beautiful addition to a home landscape.

5 Steps for Creating a Rain Garden

Step 1: Pick the spot

  • Contact local utilities by calling 811 to have them mark locations of underground wires, cables, or pipes.
  • A rain garden should be at least 10 feet from foundations and fence posts, and 25 feet from septic system drain fields and well heads.

Step 2: Outline the garden and determine depth

  • The average size of a home rain garden is 70 square feet (7 x 10 feet), but the size can vary based on how much water you want to catch.
  • Gardens should be no more than 6 to 12 inches deep.
  • Make sure the garden is not flat because you need a depression to capture water.

Step 3: Select the plants

  • Select Florida native and non-native adaptive plants that can tolerate "wet feet" in the lowest places.
  • Contact your County UF/IFAS Extension office for suggestions on plants suited to your location.
  • Determine how many plants are needed based on your rain garden size and the mature plant dimensions.

Step 4: Dig in

  • The depression in your rain garden should be marked and dug to the depth you determined in Step 2.
  • Without a depression, the rain garden will not work.
  • Make sure not to compact the soil - this is the leading cause of failed gardens
  • Place each plant at its minimum distance from other plants

Step 5: Finish up

  • Install mulch or sphagnum moss to keep weeds out and retain moisture.
  • Water the garden each day for the first week, and then gradually reduce watering over the next three weeks. After a month, normal rain should be enough to keep plants healthy.
  • Regular maintenance is required to keep your rain garden looking good and functioning well.

Rain Garden Diagram 

Tips for Managing Your Rain Garden

  • Don't worry about mosquitoes. Your rain garden should not retain water long enough for mosquitoes to have an opportunity to breed.
  • Your rain garden will contain flow from light rains, however, will fill up and overflow during heavy rains.
  • You may direct your downspout to the rain garden by digging a shallow swale or by routing it through a drain pipe.
  • If your soil lacks organic material, you may dig the depression an additional 2 to 3 inches and fill in with peat moss or compost.
  • Be creative by adding decorative items such as stones and garden ornaments to enhance your rain garden.

If you are interested in creating a rain garden, contact Environmental Services Sustainable Water Resources at (813) 744-5671 or the UF/IFAS Extension, Hillsborough County, at (813) 744-5519 for more information.

Stormwater Can Pollute Waterways
Stormwater runoff is created when rain falls on roads, driveways, parking lots, rooftops, and other paved surfaces that do not allow water to soak into the ground. Stormwater captures and transports pollutants such as pet waste, fertilizer, oils, chemicals, sediments, nutrients, and more. When stormwater cannot sink into the ground, it flows across the surface, usually ending up in streams, rivers, ponds, lakes, and wetlands.

Unhealthy stormwater transports excess nutrients to waterways that can cause algae blooms. When algae die, they sink to the bottom, decompose, and remove oxygen from the water. Fish and other aquatic life cannot exist in low oxygen levels. Sediments can cloud the water and make it difficult or impossible for aquatic plants to grow. Household hazardous wastes such as insecticides, pesticides, paints, and oil can poison aquatic life.