The pick of the plot: An evidence‐based approach for selecting and testing suitable plants to use in annual seed mixes to attract insect pollinators

Societal Impact Statement Concern regarding wild pollinator declines has increased motivation to plant pollinator‐friendly plants in gardens and urban areas, but ‘plants for pollinators’ recommendations are often anecdotal and inaccurate. Here, we use a scientific evidence base to design and test annual flowering seed mixes for bees and hoverflies. Seed mixes combining non‐native and native plants had better establishment, flowered for longer, had more pollinator visits and were more aesthetically pleasing to the public. Using a scientific evidence base to design seed mixes has the potential to enhance their societal value, by increasing their attractiveness to insects and enhancing public well‐being. Summary Annual seed mixes are frequently grown in gardens and urban areas because they are considered to be ‘pollinator‐friendly’, but choice of which plant species to include is often based on anecdotal evidence. Here, we build an evidence‐base for which plants to use in annual seed mixes to attract bumblebees, solitary bees and hoverflies. We conduct a systematic review of plant–insect interactions and use field trials to assess the attractiveness of different seed mixtures. We determined which annual plant species are attractive to bees and hoverflies using interaction data extracted from 447 peer‐reviewed articles. We then carried out field trials using four commercially available seed mixes to assess insect visitation. The plant list compiled from the literature and the results of the commercial trials were used to develop two novel experimental seed mixes that were assessed for insect visitation and aesthetic appeal. We found that seed mixes including non‐native, along with native flowering plants, had higher establishment, a longer flowering period, a greater number of pollinator visits and were more aesthetically pleasing to the public. A small number of key plant species were visited frequently in the seed mixes, and these differ between pollinator groups. Our findings can be used to provide evidence‐based guidance in the selection of plant species to be used in horticultural areas.