al wrote:
Planning on covering ceilings of porch and carport with either tongue
and groove boards or beadboard. They'll be nailed into exposed
non-structural 2X4s and will be painted rather than stained. What kind
of wood would be recommended for an application like this in south
Florida's humid climate? Thanks...

The area is covered and there is no contact with the ground or the
footing. It will be painted. Pine will be fine. Around here you
could buy poplar.