This data release contains soil-properties for one site (Nakula) on the Island of Maui and two sites (Nahuku and Lapahoehoe) on the Island of Hawaii. Maps showing the site locations are included in one of this dataset’s files (Study_sites_summary.pdf). The soil properties were compiled into three files, each formatted with comma-separated values. Field-saturated hydraulic conductivity, a hydrophobicity rating, and a preferential-flow rating were determined from soil-moisture measurements at multiple locations within two plots at the site on Maui (see Nakula_infiltration_data.csv). Dry bulk density, porosity, volumetric water content, and gravimetric water content were determined for soil-core samples collected at multiple locations and depths at each of the three sites (see Nahuku_Nakula_Laupahoehoe_soil_core_data.csv). Particle-size distributions were determined for (1) soil-core samples collected at multiple locations and depths at all three sites, and for (2) surface soil samples collected at multiple locations at one site on the Island of Hawaii (see Nahuku_Nakula_Laupahoehoe_soil_particle_size_data.csv).