Alluaudia procera, a type of cactus from southwest Madagascar, looks a lot like a crown of thorns, except that the leaves, when it has them, often grow much larger. The plant can grow rather tall -- six feet high indoors and thirty-six feet tall in its native haunts.
Alluaudia procera. See more pictures of cacti.
The stems are covered with sharp, tapering thorns or spines. When leaves do appear, they are oval and two or more inches long. Give it bright light, heavy soil with plenty of drainage, circulating air and cool or house temperatures. Drench and let dry.
It will often drop all its leaves when it decides to take a rest. When this happens, cut down on the watering until the leaves start to appear again. This is an interesting succulent and one that is not seen in every collection.
Caring for your cactus: