" Is hardening really necessary, or is this only necessary if you plan to
plant when frost is possible? I know a lot of people that just put the
seed
in the ground and used good maintenance. They had beautiful crops.

Olushola

Plants build up a waxy coating called "cutin" when exposed to UV light
which acts as a sunscreen.
Plants grown indoors have to be hardened off in order to develop some
of this cutin or the sun will fry them.

Thanks, now I understand.