What are the predominant pests and diseases afflicting gardens in the UK?

Gardening is a major pursuit in the UK, providing health and wellbeing benefits to individual gardeners, while providing important habitats for wildlife and supporting ecosystem services such as pollination. However, garden plants are afflicted by an array of pests and diseases, but until now, their importance has not been quantified, but only inferred from other sources. Here, we describe the results of a nationwide survey in the UK, designed to assess which pests and diseases gardeners consider the most important, and whether these vary across regions of the country. We found that slugs and snails and various aphids are considered the most important pests, while late blight and rose black spot are the most important diseases. Most importantly, we concluded that inferences drawn from rankings of pest and disease incidence based on enquiry data should not be taken as a proxy for importance. Many pests and diseases varied in their importance across the country and in most cases there was good agreement between regional values and current national distribution maps, suggesting that the survey produced reliable data, without regional bias.