Options for a swale


I’ve bought a property that has a swale on the north side of the lot. Its ugly! the worst part is approx 12′ wide and 30′ long. It has approx 6″ of water in it in the spring and gets a puddle in it whenever we have heavy rains. The ground is almost always damp. We have a high water table so it doesn’t ever drain away. It just sort of dries up. It’s just muck and weeds right now.
Besides ugly, its a breeding ground for Mosquitos.

I want to do something with it so it at least looks cared for and deal with the insect problem.

Any suggestions for what I can do with it would be appreciated.





Dear gardener, thank you for contacting the Toronto Master Gardeners with your question.

Swales are designed to filter the water run-off from the adjacent property and redirect it somewhere else. Look at your swale as an opportunity to plant rather than an nuisance.

One often used designed is the ‘dry’ stream bed approach. In this design, a perforated pipe is buried in the middle of the depression on top of filter fabric and covered with gravel in order to redirect excess water underground. It is then covered with river stones. You can add larger rocks to mimic a stream bed. During the spring or when raining often, the water will be absorbed and covered by the rocks avoiding a breading ground for mosquitoes.

In terms of planting you can add water-loving plants in the banks of the dry stream that will thrive in that moist environment and, absorb some of the excess runoff. Native perennials such as sedges and lady ferns can be planted near the midle. Other grasses, native ferns, Siberian irises, Bugbane (Cimicifuga), Cardinal Flower (Lobelia), Ligularia, Joe-Pye Weed, Meadowsweet (Filipendula), Turtleheads will create an interesting display in the edges and will attract butterflies while help turning your problem into a beautiful garden!

You may wish to refer to the following website for additional information: Garden Swale

If you have a chance Google images under ‘swale garden’ and you will see how beautiful and creative this type of gardening can be.

Good luck and have fun with your new project.