What it is
The stage where the plant makes its flowers. In cannabis, the buds are clusters of female flowers covered in trichomes, the tiny glands where THC, CBD and aromas (terpenes) build up.
How it starts
Photoperiod plants flower when they get 12 or more hours of uninterrupted darkness: indoors you do that by switching the timer to 12/12; outdoors it happens on its own when the days get shorter, at the end of summer. Autoflowers don't depend on light: they flower by age, at 3 to 5 weeks old, and they stay on 18/6 during flowering too: they're never switched to 12/12.
How long it lasts
Indicas, 7 to 9 weeks; hybrids, 8 to 10; sativas can take 10 to 14 weeks. Autoflowers do the whole cycle, from seed to harvest, in 9 to 12 weeks.
What it needs
The darkness has to be total: a light turned on at night or a crack can stress it and make it produce male flowers (hermaphrodite).
Phosphorus and potassium, and little nitrogen.
Temperature of 20 to 26 °C and humidity of 40 to 50 %: the buds are dense and, with high humidity, they rot from the inside (botrytis).
More water than ever: it's when it drinks the most.
Common mistakes
- Touching or moving the buds too much. Heavy pruning (it no longer recovers). Leaving humidity high. And, above all, harvesting early out of anxiety: the last two weeks add the most weight and potency.
🎮 Practice it in UnderGrow
Indoors you switch to flowering by tapping light (in climate) and setting 12/12; outdoors it flowers on its own when days have less than ~13 hours of sun (far from the equator, with somewhat longer days; near the equator, right away). From that moment the photoperiod plant stops growing: its size is set. With air humidity above 60 %, the botrytis (gray mold) chance triples.
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