This dataset contains measurements from eleven traits on 285 plants that were grown in a randomised block designed common garden trial at the UKCEH Edinburgh. Seedlings were grown from seed during 2015-2018, and the traits were measured in December 2020. The trees are from sixteen different populations across the UK. Variables measured include: stem length, stem diameter, stem angle, main stem branches, needle length and width, extension, number of stems, number of internodes, length of internodes, and total spread. This data was gathered as part of a project on juniper conservation genetics that also includes an analysis of the population genetics of UK junipers. The main goal of the project is to evaluate the standing genetic variation of populations using both quantitative and population genetic analyses. Full details about this nonGeographicDataset can be found at https://doi.org/10.5285/330cf3ac-21c3-4fa8-ab76-528f8cb2fbb8