Advanced techniques for experienced growers: crop steering, far-red light treatment, UVB supplementation, terpene manipulation, and IPM rotation schedules.
[{"topic":"End-of-Day Far-Red Treatment (Pfr Conversion / Emerson Effect)","content":"WHAT IT IS: Blasting 730nm far-red light for 10-15 minutes at the END of the light cycle (just before lights off). This converts Phytochrome Pfr back to Pr, telling the plant night has arrived faster. Also called the 'Pfr conversion technique' or 'far-red initiated dark period'. BENEFITS: (1) Can shorten flower cycle by 5-7 days (run 13/11 instead of 12/12). (2) Increases internode stretch in veg (useful for SCROG).
(3) May boost trichome production. (4) Faster flower initiation. PROTOCOL: Run 730nm far-red at 50-75 μmol/m²/s for exactly 10-15 minutes at end of day. Don't run it during the main light cycle — it needs to be the LAST light the plant sees. Some growers also do beginning-of-day far-red (5 min at lights-on) to wake plants faster.
Crop steering uses irrigation, EC, light, and temperature to push plants toward vegetative growth (bigger leaves, stretch) or generative growth (more flowers, oils, trichomes). It is the single most impactful technique for maximizing yield and quality in controlled environments.
Yes — a 10-15 minute far-red (730nm) blast at end-of-day converts phytochrome Pfr to Pr, signaling the plant that night has arrived. This can shorten flower by 5-7 days, allowing 13/11 light cycles instead of 12/12.
Studies and experienced growers report 15-30% increases in trichome density with controlled UVB supplementation in the final 2-3 weeks of flower. Results vary by genetics. Always wear UV-protective eyewear when UVB lights are running.