Circadian Rhythm Expression

Circadian rhythm expression in cannabis refers to time-dependent variations in terpene volatility and aromatic compound emission patterns across a 24-hour cycle. Plants in controlled environments often show measurable shifts in headspace volatility—typically peaking during light hours and declining during dark periods—due to stomatal activity and metabolic cycling. This phenomenon is influenced by cultivar genetics, environmental conditions (light intensity, temperature, humidity), and developmental stage. Breeders and cultivators document these patterns to understand peak harvest timing for aroma preservation and to select for stable terpene expression across day/night cycles. The trait is increasingly studied in indoor breeding programs where environmental control allows precise observation of aromatic compound dynamics.

Breeders working in controlled-environment genetics programs monitor circadian terpene release patterns to select lines with stable, consistent aroma profiles independent of harvest time. Understanding this trait helps optimize drying protocols and identify cultivars with resilient aromatic expression under variable light and temperature regimes.