18 6 Photoperiod

An 18-6 photoperiod refers to a light cycle of 18 hours on and 6 hours off, commonly used during the vegetative growth phase of cannabis cultivation. This lighting schedule is frequently employed in indoor growing operations to promote leafy, vigorous growth before flowering is induced. The 18-6 cycle sits between the more aggressive 24-0 continuous light and the standard 16-8 split, offering a balance between growth stimulation and energy efficiency. While not an aroma or terpene profile itself, photoperiod management directly influences plant development rate and secondary metabolite expression, which breeders and cultivators study to optimize phenotype expression. Different photoperiods can affect how quickly plants accumulate terpenes and cannabinoids during specific growth windows.

Breeders use controlled photoperiod regimens like 18-6 during selection and stabilization phases to standardize plant behavior across generations. Understanding how specific genetics respond to 18-6 lighting helps breeders identify fast-maturing varieties and assess stability traits before moving plants to flowering schedules.