What is a weed? We generally think of it as a ‘plant in the wrong place’. But what if we viewed these plants as signs of the ecology in which they are embedded? In this blog, Chris Maughan discusses a recent participatory study exploring the use of ‘plant bioindicators’ by UK farmers, and the publication of a new Bioindicator Field Guide. Underlying this are questions of how compatible are plant bioindicators as part of a farmer-centred, agroecological approach to soil management? And how likely are farmers to start using them as a way to engage more deeply with land they steward?