Dryback
The decrease in a growing substrate's water content between irrigation events, commonly tracked as a change in volumetric water content.
Dryback describes how much water a substrate loses after irrigation and before the next irrigation or before the next day's first event. Sensors commonly express it as a change in volumetric water content or substrate water content.
Its size and timing reflect plant water use, substrate volume and hydraulic properties, root development, climate, and irrigation strategy. The same percentage can represent different amounts of water in different containers or substrates.
Cannabis cultivators use dryback trends as one input in crop steering Crop steering The deliberate use of irrigation, root-zone conditions and climate to influence the balance between vegetative and reproductive growth. . A change in dryback does not identify its cause by itself, so it should be interpreted alongside irrigation volume, runoff, climate, and plant development.