Introducing native plant species to highly modified urban sites
is a promising measure to enhance urban biodiversity (Fischer
et al., 2013). However, since swales are categorized as civil
engineering structures, related design and maintenance are often
strongly regularized. The Berlin Standard for Swales, for example,
comprises 60+ rules, including a rather limited standard for
greening (BWB, 2012). By further developing such regulations,
biodiversity-friendly interventions can be promoted to enhance
the multi-functionality of urban swales (e.g., by allowing seeding
or planting a broad array of native species).