Laissez le sol respirer

Préserver la biodiversité et utiliser le sol comme réserve d’eau.

Des milliards d’organismes prospèrent sous nos pieds, nécessitant de l’eau et de l’air pour survivre. Lorsque des surfaces imperméables comme l’asphalte recouvrent le sol, ces organismes n’ont plus accès aux ressources vitales nécessaires à leur survie. En préservant les espaces ouverts, on favorise un écosystème souterrain plus sain et on soutient la santé des plantes en surface. Les précipitations, l’évaporation et la collecte de l’eau forment un cycle hydrique fonctionnel. Les surfaces scellées perturbent ce cycle, entraînant l’écoulement de l’eau de pluie vers les égouts, ce qui peut provoquer des inondations ou des îlots de chaleur. L’utilisation de matériaux perméables tels que les copeaux de bois, le gravier ou les pierres à pores ouverts dans les jardins piétonniers aide à atténuer ces problèmes.

Soil acts as a water reservoir 

Amidst climate change and the corresponding increase in extreme weather events such as heavy rainfall or prolonged dry spells, it has become increasingly important to manage rainwater in the garden. “Open” ground can absorb and store rainwater well, with excess water infiltrating into the groundwater, concluding the water cycle.  

If the soil is sealed with an impermeable layer (e.g. with paved stones), rainwater is unused and flows back into the sewer or causes flooding in other areas. The rainwater is irretrievably lost for the soil, plants, and groundwater formation in this garden. Therefore, the goal in every garden should be to close the water cycle and keep rainwater in the garden system.  

Preserving Organism Diversity in Soil 

Sealing the ground interrupts the exchange of air and gases between the soil and the atmosphere.  Countless soil organisms die due to the loss of rainwater and the transport of gaseous substances. This can result in a decline in soil fertility, as it can only be created through the work of a diverse group of organisms.  

What can gardeners do? 

• Design walkable garden areas (seating areas, playgrounds, etc.) in a nature-friendly manner, i.e. using wood chips, permeable gravel, grass grids, etc.   

• Reduced sealed sidewalks... 

  • ... by narrowing their surface area, since not every garden path requires the width of a sidewalk. 

  • … by reserving them for certain paths only, e.g. to the compost, and using individual steppingstones whenever possible 

  • … by paving main paths around the home with permeable porous stones or grass pavers, using a mixture of topsoil (30%) and sand (70%). Winged insects can use this area for nests, while plants germinate in the crevices, creating a harmonious mixture of stone and greenery.  

Special Feature: Green Roofs 

Green roofs can be created to offset the impermeable areas caused by homes and garages. These spaces provide a reliable habitat for many plants and animal specials instead of remaining barren, desolate areas. Additionally, these roofs act as buffers for extreme weather events by capturing rainwater and improving the surrounding microclimate through evaporative cooling during heatwaves. The greenery also acts as additional insulation, keeping buildings cool in the summer and reducing heat loss in the winter.   

Those wishing to green their roof must inquire about their building’s load-bearing capacity first and seek advice from professionals regarding drainage as well as the substrate and plant selection. The practical implementation and subsequent Maintenace work (close to none) can be carried out independently. Smaller roofs, such as bin covers or bicycle sheds, can be greened entirely by yourself using lots of imagination. And remember, every square meter of green space matters! 

Tip:  Even planting a bit of moss can store around 15 l water / m².