What is a rain garden

Essentially, it is a flowerbed that collects water runoff.

What a rain garden is not

A rain garden is not a pond. It is not impermeable. It does not retain water. A rain garden is not a swamp. The substrate under the plants is 50% sand and does not retain water. Water seeps into the soil, contrary to the swamp, where backwater remains on the surface.
A rain garden doesn’t attract mosquitoes. Dr. Jacques Boisvert, an expert in biting insects, believes that in the Quebec context there is little risk associated with the presence of water on a site if it flows out in less than 7 days. To be safe, it is recommended to reduce this delay to 4 or 5 days.  However, the rain garden gets emptied in 24 to 48 hours.
Contrary to what we sometimes hear, the rain garden is not a nest for bugs!

Un jardin intelligent aménagé à Waterloo - photo Marilou Asselin