Hydrology of Horticultural Substrates: II. Predicting Physical Properties of Media in Containers

Abstract

Handling and preparing growing media can have pronounced effects on the “intensity variables” bulk density and equilibrium volume wetness through changes in pore size distribution. These changes in turn affect the container “capacity variables”: the absolute amounts of medium, air, and water in a container. A nonlinear moisture retention function was combined with container geometry in an equilibrium capacity variable (ECV) model that provided accurate predictions of total porosity, container capacity, air space, unavailable water, available water, and solid fraction for several container-medium combinations.