In addition to important recreational areas such as the sunbathing lawns and grassy areas on the banks of the Rhine in Mainz, the embankments that are not mowed—or are mowed late—are also important. Although these are often referred to as "weeds," they are home to native plants that, unlike cultivated plants, have evolved over thousands of years alongside the native wildlife.

At first glance, this inconspicuous vegetation may not appear particularly noteworthy, but it is extremely valuable to butterflies, bees, and many other animals. In city centers, where flowers are scarce, it provides an irreplaceable source of food. The insects then fly out and pollinate our crops—and if you look closely, you can experience nature right in the middle of the city.
Especially in autumn, when other areas have long since been mowed, the plants known in technical jargon as "ruderal vegetation" provide a last source of food. Butterflies and wild bees also need the remaining stalks to hibernate. Birds, in turn, peck at them to secure their winter food.