re: Can I pour my concrete patio floor directly over dirt?

In the few patios I’ve helped form and pour, no gravel was used. Just made sure to scalp/de-grass the area and poured over dirt. Buddy of mine is in commercial concrete, and he was the unwillingly assigned supervisor for our small patios.

So I’d say that’s fine.

ETA: we tossed in some thin sheets of rebar before we poured.