Ponerorchis is a genus of terrestrial tuberous orchids in the Orchidaceae family that is sometimes included in the genus Orchis.
Ponerorchis graminifolia is very easy to grow; the biggest danger is too much water and thence rot. After they've flowered, they'll stay in growth for a long time then just go to sleep with the fall. At this point I put the pot in the greenhouse and don't give them a drop of water until spring rolls around again. They are happy bone dry in the pot. If you knock them out, be prepared to play hunt the tuber; they are like many Orchis that gather a coating of whatever medium they are in that very effectively camouflages them. Treat them like a pot of Rhodohypoxis. Description and first photo by John Lonsdale.
This plant is sometimes called Orchis graminifolia. This species is very popular in Japan where it has been grown since the Edo period by Samurai and is now grown in small orchid pots and displayed with many fancy cultivars selling for outrageous sums of money. Information supplied by Matt Mattus who grows this plant in a cold greenhouse in New England.