Horrida is in its name and and with good reason. Despite being an exceptionally cool looking plant, it is also one to be treated with care. A South African cactus like shrub with blue/green ridged, spiny stems that produce solitary green flowers during the warmer months. The spines are quite formidable and trust me, from a little accident I once had with a mature plant, extremely painful. Also, this dangerous plant has a white milky sap. It is very poisonous, DO NOT get it in your eyes or mouth, even burning the dried stems can blind you so one to treat with care. Despite the danger aspect mature plants are highly architectural and quite stunning. Can usually tolerate down to -4c if the roots are dry so may be able to survive the average winter in zone 9 coastal areas if given a sharply drained soil. Otherwise maintain in a pot, and get someone else to bring it inside for winter.
Sent as a young plant in a 5cm Pot.
Additional photo By Stan Shebs, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=3232082