Where can I find a white EPIPHYLLUM Orchid cactus, also known as Cactus Queen of the Night or Oxypetalum Cereus?
You are seeking a wonderful plant! Garden centres or nurseries specializing in exotic plants may have them. However, it would be a good idea to contact the Toronto Cactus and Succulent Society, since their members may have some for sale (sadly, you’ve just missed their annual plant sale, which is held the 1st Sunday of June) and certainly, they will have some recommended vendors, including online sources. You will find their web site here.
Good luck finding this special plant.