Light Dependency

Light dependency in cannabis refers to photoperiodism—the plant's ability to regulate flowering based on light cycle length. Cannabis contains both photoperiodic-sensitive and photoperiod-independent (autoflowering) genetics, with light exposure duration triggering flowering transitions in traditional cultivars. This trait is controlled by complex circadian and hormonal pathways rather than a single terpene, though monoterpenes and sesquiterpenes influence circadian regulation in plants generally. Breeders distinguish between short-day plants (flowering under ≤12 hours light) and day-neutral varieties when designing cultivar collections. Understanding light dependency is fundamental to indoor cultivation strategy and breeding for stable, predictable phenotypes.

Breeders select for either strict photoperiod dependence (for seasonal outdoor crops) or photoperiod independence (autoflowering lines) depending on target market and cultivation environment. Light-dependency stability is a key quality metric when stabilizing new lines or creating feminized seed stocks.