💡 Listen to learn:

• What senescence actually is — and why guiding it matters more than forcing it
• How to taper environmental cues (light, temp, RH, VPD, CO₂) without shocking the crop
• Why extreme “flushing” or 48-hour dark periods are outdated
• How color expression works and when anthocyanins are worth chasing
• The right way to manage root zone EC during the finish
• How airflow, canopy thinning, and uniformity protect quality and drying consistency
• Why trichomes should drive your harvest timing
• Data to track each harvest to refine finishing cycles over time

0:00–4:20

• Senescence = the plant’s genetically programmed aging and biochemical refinement phase

• Peaks in cannabinoid + terpene development

• Outdoors, shortening days and cooler nights drive senescence

• Senescence isn’t the plant dying — it’s perfecting what it has built

4:20–7:15

• Growers often stack stressors late (pruning + EC shift + temp change at once)

• Many facilities harvest too early due to tight scheduling

• Early cutting reduces terpene, potency, and maturity

• Final weeks are about refinement, not heavy intervention

7:15–11:55

• Trichome progression: clear → milky → amber

• Ideal target: mostly milky, some amber

• Excess new white pistils signal incomplete maturity

• Fan leaf fade = carbohydrates relocating to resin glands

• Avoid sending any late “reveg” signals

11:55–17:06

• Reduce DLI by 10–25% to avoid photo-oxidative stress

• Taper CO₂ from 1200–1400 ppm down to ~650 ppm pre-harvest

• Lower temps 3–5°F in final week

• Maintain 50–55% RH; avoid deep swings

• Allow modest VPD rise without overdrying

• Cooler late-stage temps help retain volatile terpenes

17:06–20:28

• Color = genetics + environment

• Anthocyanins are temp-sensitive and highly plastic

• Some cultivars purple even in warm rooms; others resist

• Extreme cold to force color can reduce yield and slow photosynthesis

20:28–21:54

• No evidence darkness increases THC

• Benefits come from reduced temperature, not lack of light

• Better: taper light + temp rather than shutting lights off entirely

21:54–23:54

• Reduce or pause irrigation 12–48 hours before harvest

• Helps start internal drying if dry rooms are undersized

• Avoid wilting; maintain some light for transpiration

23:54–29:32

• Full RO flushes cause osmotic shock and reduce yield

• Modern method: gradual EC taper, not starvation

• Reduce nitrogen while maintaining calcium for structure

• Avoid violent EC swings; controlled stress is better than deprivation

• “Flushing benefits” mostly came from reduced nitrogen, not true flushing

29:32–35:32

• Strong airflow prevents botrytis and dew-point condensation

• High airflow supports wider day–night temp ranges safely

• Best defoliation window: 3–5 days before harvest

• Uniform, light defoliation beats extreme thinning on select plants

• Improves drying consistency and reduces bud rot

35:32–37:39

• Taper everything: EC, light, temp, CO₂, RH

• Let trichomes drive harvest timing

• Track data each run: yields, cannabinoids, terpenes, environmental tweaks

37:39–41:28

• Ethylene influences ripening across many crops

• Cannabis produces ethylene — its role in finishing may be important

• ABA + ethylene interactions could explain ripening behaviors

• Potential future avenue for finishing optimization