In my opinion, both the replies I saw to the cultivation advice were
correct, as far as they went.
In general, Pinguiculas from Mexico seem to like to be dry with good air
circulation and obtain much of their water as cloud vapour or dampening
of the soil. Even when enveloped in cloud, the atmosphere is not
lkikley to make soil sodden and, as was said, several species are either
epiphytic or act as if they were, attached to vertical rock faces.
Pings from other locations mostly (but not all) like to have varying
degrees of dampness but very seldom do they like much water or permanent
really wet soil near their leaves or neck. (I have to be careful here,
it's very dangerous to generalise about conditions for Pings, many are
proving to be niche growers).
However, P. primuliflora seems to like to be in a far more humid
atmosphere than most Pings. So short of using ionisers to create moist
air, or providing misting, a small layer of live sphagnum moss can be a
very healthy medium on which to grow P. primuliflora. Be warned though,
live sphagnum is not suitable for many other Pings.
Regards
Paul