Enhancing gardens as habitats for flower-visiting aerial insects (pollinators): should we plant native or exotic species?

1. Domestic gardens typically consist of a mixture of native and non-native plants which support biodiversity and provide valuable ecosystem services, particularly in urban environments. Many gardeners wish to encourage biodiversity by choosing appropriate plant taxa. The value of native and non-native plants in supporting animal biodiversity is, however, largely unknown. 2. The relative value of native and non-native garden plants to invertebrates was investigated in a replicated field experiment. Plots (deliberately akin to garden borders) were planted with one of three treatments, representing assemblages of plants based on origin (native, near-native and exotic). Invertebrates and resource measurements were recorded over four years. This paper reports the abundance of flower-visiting aerial insects (‘pollinators’) associated with the three plant assemblages. 3. For all pollinator groups on all treatments, greater floral resource resulted in an increase in visits. There was, however,...