The data supports the paper "Local and landscape factors shape alpha and beta trophic interaction diversity in urban gardens". It provides (1) the host-natural enemy interaction networks and network metrics between cavity-nesting bees and wasps and their natural enemies, and (2) the explanatory variables reflecting urban intensity, temperature, habitat amount and management intensity. The data is part of the BetterGardens project. It was sampled in 85 allotment and home gardens in the ctiy of Zurich in 2015 using standardized trapnests.