Why the days change
The earth is tilted: for half a year one hemisphere gets the sun more head-on (summer, long days) and for the other half, at an angle (winter, short days). The farther from the equator, the bigger the difference: in southern argentina, a summer day has more than 16 hours of sun.
What happens to the plant
Photoperiod plants use that clock: they grow with the long days of spring and summer, and when the days drop below about 13 hours (at the end of summer) they flower. That way, in nature, the seeds are ready before winter.
When to sow
The ideal is to sow in spring: the plant has the whole summer to grow and flowers at the end. If you sow late, it flowers small. Autoflowers don't depend on this: you can do several a year, as long as it isn't cold.
🎮 Practice it in UnderGrow
Outdoors the year has 360 game days (15 real days) and the sun hours depend on the season and your province (in mendoza, from ~10 to ~15 hours; in tierra del fuego, from ~8 to ~18). Outdoor photoperiods flower on their own when days have less than ~13 hours of sun (far from the equator, with somewhat longer days; near the equator, right away: the panel says how long is left). The seasons depend on your hemisphere. Indoors, the house climate changes too: colder in winter and hotter in summer.
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