Why every night counts
Weight: Chrysanthemum greenhouse work is cited: skip nights and flower size and weight drop. Cannabis behaves as a long-night plant in the same way.
Loose buds: Inconsistent dark makes flowers elongate and open up.
Herm risk: A run of interruptions can stress a plant into male flowers on a female.
Indica note: Once triggered, some indicas mind an occasional blip less than sativa-leaning plants, but you still should not treat night as optional.
Longer nights to finish
Heavier flower
Plants that already started will flower harder if you lengthen the dark
Ripen
10 hours of light and 14 of dark pushes indicas and long sativas to finish faster
After establishment
The book suggests adding about an hour of dark after the first 3 or 4 weeks of flower
Do not starve light early
Use the longer night as a finish tool, not as a weak veg substitute
Far-red as a jump start
Two-hour lag
After lamps go off, the hormone takes about two hours to reach its active form
730 nm
A brief far-red dose at lights-off can flip that hormone almost immediately
Outdoor math
A few seconds of far-red after dusk can make a 9-hour night act more like an 11-hour night
Repair
Far-red after an accidental light leak can help put the hormone back on the flower side
Working in the dark
Green
Plants reflect much of the green band and do not use it to time flower. A green CFL or LED lets you work
Not green
HPS, white fluorescent, and metal halide all carry red and will reset the night
Hat clip
A green LED on a brim keeps both hands free
Rule
If the light is not green, stay out until the timer says day