Some physical and mechanical properties of a sample of ‘Granex-Grano’ type sweet onions were examined in an attempt to more deeply understand the conditions under which those onions may most appropriately be grown, harvested, stored, processed, shipped, and marketed. Those onions evaluated had a mean mass, surface area, volume, and density of 98 g, 111 cm2, 95 cm3, and 1 100 kg/m3, respectively. The overall mean equatorial diameter was 62 mm and the mean polar diameter was 42 mm. Of the mature onions examined, 59% of the onions were oblate and 41% were prolate. Crushing load and puncture force are indications of mechanical strength of the onions to withstand mechanical harvesting and postharvest handling. Onions evaluated from this study had a mean crushing load of 26.4 N and puncture resistance of 25.0 N.