A Pencil Cactus, Euphorbia tirucalli, is not a cactus plant at all but rather a member of the euphorbia family like a Poinsettia. This unique looking plant, native to Africa and India, is also referred to as Indian Tree Spurge, Naked Lady Plant, Aveloz, Milk Bush Plant, and Petroleum Plant. The green succulent stems of a Pencil Cactus, which are about the width of a pencil, branch upwards in an almost geometrical pattern. A Pencil Cactus grows quickly and can reach a height of 10′-15′ outdoors and up to 6′ in an indoor container. Although this is an easy care plant that just needs bright light and a little bit of water to do well, it does have a downside. All parts of these plants are considered poisonous and should be kept away from pets and children. Read more about common houseplants that are poisonous in Don’t Feed Me to Your Cat: A Guide to Poisonous Houseplants. This is a very different looking plant that I wouldn’t call beautiful and lush, but it is quite a conversation piece.
After taking a stem cutting from a Pencil Cactus Plant for propagation, dip the cut end of the stem in fresh water to stop the flow of the latex, sap. Allow the cut end of the stem to dry out for a week until it forms a callous on the tip. When the Pencil Cactus cutting is ready, pot the cutting in moist sand or in some cactus soil.
Repotting a Pencil Cactus Plant is a little tricky because of the danger of root rot due to over-watering. You should only re-pot a Pencil Cactus Plant when it is really necessary and then only during the warm months. Be sure the soil is very dry before you start, then gently remove the Pencil Cactus from its pot. Brush off the soil from the roots and remove any dead roots. If you accidentally make any cuts in the stems of the Pencil Cactus, immediately treat them with a Fungicide. Put the Pencil Cactus in its new container and spread out the roots. Fill in around the roots of the Pencil Cactus with moist succulent or cactus soil. Allow the soil in the pot to dry-out for a week or so, then begin to water lightly to reduce the risk of root rot. Since the Pencil Cactus is in a larger pot, it will take longer to try out.
The leaves on the stems of a Pencil cactus Plant naturally fall off very quickly. You are not doing anything wrong. A Pencil Cactus usually just has its long thin cylindrical succulent stems.