This dataset contains experimental results from my PhD research on plant root-soil–mucilage interactions and their effect on penetration resistance. It includes raw rheometer measurements, processed penetration resistance curves, and energy calculations for different soils, water contents, mucilage types, and needle geometries. Analysis files provide final plots, energy summaries, and statistical evaluations (t-tests/ANOVA). R code used for significance testing and Python code for cavity expansion modelling (Chapter 3 only) are included. The dataset is organized by chapter to enable full reproducibility of all figures, calculations, and interpretations presented in the thesis.