Paphiopedilum violascens is a relatively rare species in cultivation. It can be somewhat challenging to grow. This is probably why it is seldom offered for sale.
This species is native to New Guinea at low elevations. As a result there is no distinct cool season like many other slippers experience. There is also no dry season as the habitat receives over 100″ of rain per year. Jay’s site has more details on this species.
We grow these warm and with plenty of water in a well drained mix.