Disocactus ackermannii or Orchid cactus is a perennial epiphytic cactus.
It flat, green stems that have scalloped edges and in spring it produces large and wonderfully fragrant waxy funnel shaped red flowers that last for 3-4 days.
They are frost tender and grown in conservatories or inside in cooler climates.
In warmer climates they grow will grow well outside in well drained Orchid type potting mix featuring lots of pine bark chips.