Potential benefits of incorporating arable wildflowers into living mulches for sustainable agriculture

Background: As agriculture has intensified, many once-common
wildflowers have declined in arable landscapes, which has widespread
implications for associated ecosystem services. The incorporation of
sustainable practices, for example, growing living mulches (in-field,
non-crop plant ground cover, maintained during the target crop growing
season), can boost arable biodiversity, but few wildflower species have
been utilised in this context.  Aims: Our aim was to
determine the suitability of arable wildflower species, once considered
weeds, for use as living mulches. Methods: We first screened a
number of arable wildflower species for germination when growing with a
common cereal, barley (Hordeum vulgare). We then grew two (Centaurea
cyanus and Scandix pecten-veneris) in pots in a
glasshouse with and without barley, and grew barley alone to test the
impact of the wildflowers on barley growth and biomass.
Results: Neither of the wildflowers significantly negatively
impacted barley biomass. Barley initially facilitated germination
in S. pecten-veneris, but ultimately suppressed the above-ground
biomass of both wildflowers. However, both wildflower species were able to
coexist alongside barley. Conclusions: Our experiment provides
evidence that wildflowers that were considered weeds in traditional
agriculture have the potential to be grown alongside barley and could be
incorporated as part of a living mulch.