Evaluation of insects' attraction to garden plants in a semi-arid region of Spain

Urban environments can provide essential resources for food, nesting and hibernation for insects. Green spaces in cities often exhibit higher flower diversity and lower pesticide levels compared to these properties in rural areas. Although gardens are typically designed for aesthetic purposes, growing interest in their benefits for wildlife has driven research on pollinators' attraction to plants, with the aim of enhancing urban biodiversity.

To our knowledge, no published studies have evaluated insects' attraction to garden plants in the Iberian Peninsula. This study aimed to identify the garden plants and shrubs most suitable for supporting insects in southeastern Spain. Weekly observations were conducted of flowering plants in four urban gardens in Murcia between mid-April and mid-May 2024. For each plant and shrub species, two patches of a similar size were monitored for two minutes each. Insect visitors were recorded and classified as “honey bees”, “wild bees”, “syrphids”, “non-syrphid flies”, or “others.”

A total of 31 plant and shrub species were sampled, of which only 8 were native to the Iberian Peninsula. No significant difference was found in the number of insects attracted to native versus non-native plants. Lavandula dentata, Salvia officinalis, Zygophyllum fabago, Phlomis purpurea and Pyracantha coccinea attracted the highest numbers of insects. These findings provide practical recommendations for promoting insect-friendly gardening in a semi-arid Mediterranean region, highlighting the potential of urban gardens to support insect biodiversity.