Abstract
A standard 1:1 v/v pine bark and sand potting medium was characterized physically by particle size distribution, bulk density (BD), total pore space, porosity at 50 cm H2O tension and porosity at >50 cm H2O tension. A potting medium identical to the standard was constructed from component milled pine bark and sand particles. Phaseolus lunatus L. ‘Jackson Wonder’ plants grown in the 2 physically similar media, under a standard cultural program, were essentially identical. Construction of a potting medium from a prescribed screen analysis provides a means to quantify variation which exists within a medium assumed to be uniform.