If you want to create a wetland in your garden, or even just a small wetland/swamp bed, first take a good look around. Maybe there is already a natural depression where rainwater collects and runs away. Or you already have a pond in the garden, in whose edge area (see picture below) a marshy bed fits perfectly of course. However, it should not be in direct connection with the pond, otherwise nutrients will diffuse into the pond over time, and the algae will be happy.
Now you just have to make sure that the water in this area does not seep into the ground so quickly. You can do this in the same way as when building a pond. Either you seal with clay or loam, i.e. natural materials, or you use an EPDM pond liner for this purpose. For ecological reasons, do not use PVC foil if possible. If the soil is heavily interspersed with stones, it is advisable to install a protective fleece between the substrate and the liner.
Newly created pond with pond edge community IMG_5799.JPG