This dataset contains measurements from a 12-month field experiment in the UK assessing the degradation, microplastic generation, and environmental impacts of seven plastic mulch films exposed above and below ground, alongside associated soil, environmental, and material property data. Below ground films were either in fine or coarse mesh bags (filled with 20g soil and 5x5 cm plastic piece) to allow only microfauna or micro-, meso-, and macrofauna interaction. The aim of this experiment was to identify the degradation rates of mulch films under UK weather conditions, their microplastic generation rates, and their effect on soil properties and microbial communities (microbial data has been deposited with NCBI: PRJNA1229197). The details can be found in the lineage field and the supporting document. Full details about this dataset can be found at https://doi.org/10.5285/76322cd6-a420-42e1-9495-5ed929b1c289