Problems in the Analysis of Organic and Lightweight Potting Substrates

Abstract Most potting mixes currently used for raising greenhouse crops, vegetable transplants, and hardy ornamental shrubs in containers do not contain mineral soil; these mixes are often known as “soilless”, “lightweight”, or “artificial” media. Their popularity has increased steadily over the last 3 decades, principally for reasons of convenience or economic advantage. The chemical and physical characteristics of these media are, however, very different from those of the traditional potting mixes based on mineral soil.