Rain Gardens

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Don't Let Rainwater Go Down the Drain!

Capture water from your downspout and create your own miniature wetland.

Rainwater from your rooftop is generally relatively pure and free from chemicals such as chlorine found in municipally treated water. It also tends to be warmer than water straight from the hose. All in all, it's a better choice for growing some of the more sensitive moisture-loving native species.
By diverting water from your rooftop into a bog garden or rain barrel, you will reduce stress on local streams and culverts caused by the influx of water delivered via storm sewers. The volume and force of this water, particularly after mixing with oils, pesticides, animal wastes and other pollutants washed from impermeable surfaces, can be devastating for local riparian habitats and fish spawning grounds.

Wild plants belong in the wild...but there is often little wild left near urban areas. In such cases, native plant gardens can help to lessen the void. Suburban gardens, however, don't always provide the range of conditions that may have been present before development. Hot, sunny spaces suitable for meadow re-creations are abundant in newer developments and shaded woodland settings can be found in more established neighbourhoods. Wetland conditions, however, are rare as developers strive to remove water via grading, guttering and storm sewers.

Creating

It is possible to create artificial wetlands in even small yards.  Ponds are popular in gardening circles and can provide habitat for dragonflies, turtles, toads and frogs.  Standing water, however, isn't necessary to encourage the growth of wetland species.  In many regions, sufficient moisture can be collected from rooftops or oter impermeable surfaces (driveways, patios, walkways).

  • Grading can direct water to low spots in the garden.
  • Cutting out the bottom of a sloped driveway and backfilling it with gravel can allow water running off the driveway a chance to infiltrate the ground.
  • A simpler method calls for cutting the downspout and re-directing its flow onto the lawn or garden or into a rain barrel or into a specially-constructed “bog” – a more or less continually moist patch of soil.

Once completed, a rain garden will look like any other, but you won't have to water it except during the most severe droughts.

  1. Simply outline the shape of your bog garden and dig it out to a depth of about 3 feet. The bottom of the hole should slope slightly away from your foundation to direct any excess moisture into your lawn or garden.
  2. Next line the hole with plastic and poke a few holes several inches above the bottom to allow excess water to drain out—you’re not creating a pond after all.
  3. Refill the hole with a mixture of the excavated soil, peat moss, and other organic materials you have on hand (compost, pin needles). Many bog plants like a slightly acidic soil.
  4. The soil should be somewhat mounded to allow for settling.
  5. Wet the mix thoroughly.
  6. Cut your downspout and attach an elbow, and if necessary, an extension, to direct rainwater into your bog garden and away from your foundation. Most hardware stores carry an extensive array of downspout extensions.
  7. Place a few small stones or other hard material under the waterflow of your downspout to create a splashpad.
  8. Now add your plants and get ready to enjoy a truly beautiful and unusual garden.

Just as in ponds, most gardeners wish that they’d made their bog garden bigger. The range of plants of thrive in them is astounding and it is tempting to try to squeeze more in than your space can accommodate.

Bog gardens are a low maintenance alternative to rain barrels and an effective water conservation technique.

Conserving

Water conservation is mandated in many drought-ridden areas of North America and is important even in areas receiving adequate rainfall.

Precipitation is a valuable resource. It is essential to plant growth, recharges groundwater and replenishes water bodies. Raindrops aid reproduction in mosses. Relatively pure, it is healthier than municipally-treated water for our native plant gardens…yet this essential commodity is regularly flushed into sewers.

Collecting precipitation, whether via rain barrels or simply re-directing it to permeable areas of your property, can greatly enhance both your garden and local waterways.  Water is taken up by your trees, shrubs, herbs, and returned to the hydrologic cycle through evapotranspiration.  This vegetative respiration process can have a considerable cooling effect in overheated urban settings.

What isn’t used in situ flows through the ground, eventually finding its way, filtered by the soil, into open water bodies. 

In developed areas, precipitation is collected from private properties and roadways in storm sewers which then empty into local waterways. This water often carries oils, greases, pesticides, animal wastes, and other other pollutants. Concentrated in the sewer lines it rushes through openings called outfalls into creeks and rivers, causing erosion, washing out spawning beds and causing other environmental damage.

Connecting

By disconnecting your downspout from sewer lines, you can re-connect with nature.  There is an abundant supply of native plants that thrive in moist or intermittently moist conditions and which provide habitat for a further abundance of wildlife.

Native plants will thrive without further assistance once established in the right location.   Please visit our Plants database to select native species suitable for wetland conditions.