I have a bit of a collection of terrestrial orchids and it looks like I may well be posting many of them on here.
I have aleady posted a thread on Disa which grow alongside my carnivores, so I'll continue the theme with a couple of Epipactis that enjoy damp / wet conditions.
Epipactis gigantea is a North American native with the common names Stream Orchid and Giant Helleborine. Very easily grown in a basic Sarracenia medium and conditions. Height can be anything from 30cm (12") to a Metre (40").
There is also a purple/maroon leaved cultivar commecially available.
Epipactis royleana is an Asian member of this orchid group. It appears to be quite happy grown as above. I have seen heights of 45cm (18") quoted for this species and to date my own plants have peaked at 35cm (14").