Insufficient calcium (Ca) or magnesium (Mg) in the diets of humans and animals has negative effects on health. Knowledge of the concentrations of Ca and Mg in edible crops can help inform the formulation of appropriate diets. There are large differences in shoot concentrations of both Ca ([Ca]_shoot) and Mg ([Mg]_shoot) between angiosperm orders. For example, relative to other angiosperms, commelinid monocot species generally have lower [Ca]_shoot and [Mg]_shoot; species from the Cucurbitales, Malvales and Brassicales generally have higher [Ca]_shoot and [Mg]_shoot; and species from the Oxalidales and Caryophyllales generally have higher [Mg]_shoot but similar [Ca]_shoot, which results in higher [Mg]_shoot/[Ca]_shoot quotients. In this paper the evolution of the combined traits of high [Mg]_shoot and high [Mg]_shoot/[Ca]_shoot quotient in the Caryophyllales was resolved at the family level. All Caryophyllales families had high mean [Mg]_shoot and [Mg]_shoot/[Ca]_shoot quotients, suggesting that both of these traits evolved in an ancient ancestor of all Caryophyllales families.