Frost hardiness is one real advantage autos inherited from their ruderalis side, and it shows outdoors in spring. Mine have shrugged off nights near five degrees that would have stalled a photoperiod plant, though growth does slow noticeably. Anyone planning an early sowing can check the temperature tolerance notes per strain on https://turboautoflowerseeds.com since some modern crosses have lost much of that toughness. A cloche or cold frame for the first fortnight is still cheap insurance.