  Recently, two simple criteria were proposed to assess if vacua emerging from
an effective scalar field theory are part of the string "landscape" or
"swampland". The former are the vacua that emerge from string
compactifications; the latter are not obtained by any such compactification and
hence may not survive in a UV completed theory of gravity. So far, these
criteria have been applied to inflationary and dark energy models. Here we
consider them in the context of solitonic compact objects made up of scalar
fields: boson stars. Analysing several models (static, rotating, with and
without self-interactions), we find that, in this context, the criteria are not
independent. Furthermore, we find the universal behaviour that in the region
wherein the boson stars are expected to be perturbatively stable, the compact
objects may be part of the landscape. By contrast, in the region where they may
be faithful black hole mimickers, in the sense they possess a light ring, the
criteria fail (are obeyed) for static (rotating) ultracompact boson stars,
which should thus be part of the swampland (landscape). We also consider hairy
black holes interpolating between these boson stars and the Kerr solution and
establish the part of the domain of existence where the swampland criteria are
violated. In interpreting these results one should bear in mind, however, that
the swampland criteria are not quantitatively strict.
