Reddit mentions of Miniature Orchids

I would recommend trying species from the group Aerangis, Specifically Aerangis hariotiana, hildebrandtii, fastuosa, and citrata as these are low light species from very humid regions that would fit the temperature range you have.


Also try Pleoruothallids, Group includes Masdevallia - Pleurothallis - Dracula - Lepanthes - Restrepia and so on, that are warmer growing. Species from coastal Brazil will work well in your conditions provided they are also miniature in size. Dracula lotax, Pleurothallis tribuloides, and Platystele umbellata are some of the easier to find members from the group that stay fairly small while flowering regularly.


Bulbophyllum nitidum and tingabarinum are two species that are readily available and have very dramatic flowers, Bulbophyllum depressum and laxiflorum are two others with smaller blooms but are just as easy to cultivate.


Gastrochilus species, especially fuscopunctatus and dasypogon, are suited to growing very humid and warm while staying tiny and small respectively. Haraella retrocalla is a close relative and is also quite adaptable to being grown in tanks with lower light levels.


Miniature Orchids by Steven Frowine is a good reference for more commonly cultivated plants that are suitable for beginners.

If you have the willingness to grow rare and very exotic species I recommend A Compendium of Miniature Orchid Species by Ron Parsons (2 volumes). It is a very detailed book on growing some of the more unusual varieties with extensive detail on conditions and growing needs for the species described in it. it is, however, quite expensive and would be a better choice for someone intending on amassing a moderate to large collection rather than a small tank of miniatures.

If she is an indoor grower and likes miniatures, Miniature Orchids by Steven Frowine is great. Anything he writes is pretty awesome and easy to understand.