This dataset contains vegetation survey data, and nitrate and ammonium concentrations, nitrification and mineralisation rates, microbial biomass and carbon and nitrogen stock data from soils taken from an experiment based at Winklebury Hill, UK. The vegetation survey comprises total species percentage cover and species richness data from four 50 cm by 50 cm quadrats. Net ecosystem carbon dioxide exchange, photosynthesis and respiration data were measured with an Infra-red Gas Analyser (IRGA); methane, carbon dioxide and nitrous oxide data were measured using gas chromatography; nitrate and ammonium from soil samples extracted with potassium chloride; carbon and nitrogen from soils extracted with water; and carbon and nitrogen stocks measured through combustion analysis. The experiment used seeds and plug plants to create different plant communities on the bare chalk on Winklebury Hill and tested the resulting carbon and nutrient cycling rates and compared these to the characteristics of different plant functional groups. The experiment ran from 2013 to 2015 and this dataset contains data from 2015 only. This experiment was part of the Wessex BESS project, a six-year (2011-2017) project aimed at understanding how biodiversity underpins the ecosystem functions and services that landscapes provide.