Wadi with plants

One of the easiest solutions for collecting rainwater from your roof and garden is a wadi. The word wadi stands for water drainage through infiltration.

A wadi is a lowered area of the garden where water flows (via a gutter, pipe, or surface). The water then sinks into the ground. A wadi can be a low-lying lawn, but it can also be a depression planted with plants that can withstand water and drought. Not only does it look nice, but it's also good for biodiversity! A wadi with plants is also less likely to silt up than grass.

View the wildflower mixture for wadis here.

Costs

The construction and planting of a wadi costs little more than the construction of a normal garden. Additional costs may include the construction of a gutter between the downspout and the wadi.

Use of space

A wadi or a sunken lawn does not have to take up extra space.

Difficulty

For a wadi with plants, you need to know which plants can withstand drought and water. These are usually riparian plants (also known as zone 1 plants), which you can find in garden centers among the pond plants. Most types of grass are also suitable. Ask the staff at the garden center for advice.

Earthmoving

Most gardens are flat. If this is the case, you will need to dig a hole. You can often use the soil you dig out elsewhere in the garden. The garden must be low enough in relation to your home to prevent flooding during heavy rain.

Maintenance

A sloping lawn is more difficult to mow than a flat lawn. Do not make the slopes too steep. A slope is the sloping surface that you excavate. The steeper the slope, the more difficult it is to mow a grass wadi. If a wadi is well planted and has grown well after a year, it requires hardly any maintenance. Most types of weeds cannot tolerate water and drought. It is sufficient to prune the plants back at the end of winter and remove the fallen leaves. Weeds that do take root can be removed manually.

Climate goals

The planted wadi reduces heat stress. A grass wadi dries out during periods of prolonged drought and evaporates little water. The plants in a wadi remove most of the pollutants from the rainwater. This keeps the soil clean. A wadi with flowering plants is not only beautiful, but also good for biodiversity. Finally, if the wadi is large enough, all the rainwater is collected and added to the groundwater.

Biodiversity

Contribution to improving biodiversity