The design of this flowerbed at first glance seems quite simple - a bench, so what? But you cannot sit on such a bench; it is not intended for this. This flowerbed is so framed.
A hole has been made in the bench seat; a box of flowers has been inserted into it. The box can be replaced with another if desired. And the so-called "bench" is just a fence for a flower bed.
In general, the entire structure does not have to be as fundamental as in the photo. For a summer cottage, you can choose the design easier, but this is a variant of vertical gardening. The photo shows that flowers also grow under the bench.