When I first came across this little plant, it was labeled a rhipsalis; later the name hatiora came up. I have finally settled on rhipsalis hatiora salicornioides.
By either name, this is an epiphytic cactus, which means that it grows on other plants, but not as a parasite. Simply looking for a place to live, the roots of the cactus anchor it in the crotches of tree branches in the rain forests of South and Central America and parts of the Caribbean. Organic matter collects there, decomposes, and provides a light, loose growing medium for the cactus, which means you will want to use a well-draining soil when you plant it.
Rhipsalis is in the same family as other epiphytic cactus, Christmas cactus being one of the more popular ones, and orchids, which also grow on trees in the rainforests. These plants are classified as cactus rather than succulents, but they are a tad different as you can see from their growth pattern, their use of less sun and more water than most cactus, and spines that are there, but just barely.
Rainforests are called that because, well, it rains a lot in those forests, right? And there are many trees, which means there is an abundance of shade. Now, shade and lots of rain aren’t conditions usually associated with cactus, and it has been my experience with rhipsalis that is does indeed like a bit more water than other cactus. I have never put mine out in full sun, either, so for me a bit more water and a bit less sun seems to work. This little cactus may like more frequent watering, but won’t like sitting in soggy wet soil for too long.
This particular variety has yellow flowers which are blooming now. The literature says to keep them drier when they are not blooming, but check from time to time. If the branches look browner and shriveled, I would water more often.
This is a cactus with an uncharacteristic cactus look that adds a different texture and interest if you choose to put it with other cactus and succulents in a dish garden. They also look good in hanging baskets or as a specimen plant all by itself. And they are pretty when in full bloom. So you might consider adding one to your collection.