Many hidden ecological services

Rain gardens don’t just manage stormwater runoff. Here’s an amazing secret: they provide other invaluable ecological services!

1. Managing stormwater runoff

First, on top of reducing the “water hammering" intensity of  sudden showers, rain gardens improve water quality before it reaches groundwater and streams. By implementing rain gardens in multiple areas of  lake Waterloo’s watershed, we can reduce the phosphorus mineral reaching the lake. This would be a significant gain considering that 53% of the external contributions of phosphorus into lake Waterloo come from urban runoff.

Phosphorus mineral reduction is the primary goal of Les Amis du bassin versant du lac Waterloo, rain garden project

The management of stormwater is of concern to the ministry of the environment and the fight against Climate Change. Consult  the impacts of  stormwater runoff and the measures the Government of Quebec is putting in place to mitigate them.

2. Collection of the phosphorus by the rhizophere

Plants in rain gardens absorb some of the phosphorus to feed and grow. But they’re not the only ones doing this job! They actually have some very effective microscopic allies!

There is a high-performance factory embedded in  the plants’ roots. This factory is called the rhizosphere! It is formed and affected by the soil at the roots. The workers at this factory are microorganisms: microscopic bacteria and fungi.

The function of the factory (the rhizosphere) is to promote exchanges between the workers (microorganisms) and the plants. The result of these exchanges is the modification of the physical and chemical properties of the soil, among which  the absorption of part of the phosphorus. Nature never ceases to amaze us!

Learn more about the rhizosphere

The benefits of rain gardens don’t stop here.

3. Promoting biodiversity

photo Sabine Vanderlinden

“Life attracts life! Diversity attracts biodiversity. Creating a garden is giving birth to a small world full of life, reproducing on a small scale the richness of natural ecosystems. It can feed, shelter and facilitate the reproduction of useful insects, birds and other small animals," recalls Espace pour la vie Montréal.

Intelligent gardens increase the biodiversity of residential land by creating a space conducive to the flora and to the wildlife albeit at a smaller scale.














4. Attracting pollinisators

Pollination is one of the greatest gifts of nature. If we think about it for a moment, it is quite remarkable: insects, bees, butterflies, hummingbirds too, travel from plant to plant, generating pollen in the air allowing plants to produce seeds and fruits.

(The more scientific explanation is that the transfer of pollen from the stamens, the male reproductive organs of plants, to the pistil, the female reproductive organ of plants, promotes the fertilization of seeds and fruits, as per the e-magazine Du jardin dans ma vie)

Isn’t it extraordinary?

Well, rain gardens are popular with pollinating insects. Especially if your choice of plants contains fruit shrubs.

Read what L’actualité magazine wrote on permaculture.

photo Sabine Vanderlinden