A rain garden is a bed of plants specifically designed to gather storm water that can then be absorbed by the plants and the underlying soil.
- It is practical, because it is a simple way to deal with rain water as well as from water from melting snow.
- It is ecological, because it drives the water where it can do good, rather than into the streets and gutters, where it can accumulate and create various problems, such as carry fertilizers and pollutants that eventually end up in streams and rivers, not to mention overpower sewage systems and create floods.
- Many plants thrive in rain gardens, so you can turn a problem to your advantage by creating a beautiful garden.
But what exactly is a rain garden? On the surface of it, it is simply a flower bed filled with water-loving bushes and flowers. But it can also be described as a special feature of a landscaping specifically designed to collect runoff water and to dispose of it through natural means.
And how do you create a rain garden? Well, in a nutshell, there are four things you need to do:
- Pick a spot that you think would be a good location to collect runoff water. Consider a location that naturally is at a lower level than the surrounding areas. A gentle slope will naturally drive water to your rain garden. Also try to find a place close to runoff water sources, but away from your house’s foundations. You want to be able to drive water from your roof or driveway to that location, but you don’t want the water to end up in your basement. Consider installing roof gutters and using a hose to drive the water to your rain garden.
- Turn that spot into a hole deep enough to collect all your runoff water and to let it seep into the ground below (make sure there is no cable or pipe buried below ground before you start digging). Bear in mind you are not creating a water garden. The water from a rain garden must have a way to slowly escape to the surrounding soil. If your rain garden looks waterlogged two days after a downpour, then you have a problem on your hands. If you are digging your hole into clay soil, this may be a problem. You will have to find a way to let the water escape to more permeable soil. Using larger clay soil plants in or around your rain garden may help somewhat, as they will grow long roots through the clay and absorb some of the water as well as provide escape routes to the soil below. Worst case scenario, you may have to install an underdrain connected to your house’s main drain to do away with the excess water.
- Fill the hole with a rich, yet highly permeable soil mixture: 60% sand, 20% compost and 20% top soil.
- Choose water-loving plants (see Wet sun plants) and create your own flower bed design.
Rain gardens have many benefits: they protect your house, they drive excess water to where it can be used, they divert contaminants away from natural water bodies, they replenish water sources deep in the soil.
Other rain garden considerations
You may also consider ways reduce the amount of rain water that ends up as runoff water. If your driveway needs to be spruced up, why not consider paving stones. Usually set on a bed of sand, a driveway made of paving stones lets rain water be absorbed on the whole of the surface, as opposed to an asphalt or concrete driveway, where the water runs off to the side and onto your yard or into the street (not to mention into your house or garage sometimes).
Choose a sunny spot for your rain garden, as there are many water-loving plants that grow well in sunny locations. And since sun-loving plants tend to grow faster than shade-loving plants, your rain garden will drink up more and more water as years go by. Do consider native plants. They are generally better adapted to local weather conditions and more resistant to local pests and diseases.