Pencil Cactus

Beginner’s Guide to the Pencil Cactus or Milk Bush Plant

The pencil cactus (Euphorbia tirucalli), also known as milk bush, is not really a cactus at all. This non-cactus is actually a tropical plant native to Africa and India, and in the plant world it is a part of the Euphorbia family. Successfully growing a pencil cactus is no different that growing any other tropical plant. In fact, this particular plant is quite easy to grow because it does not require much care at all. The basics – good soil, a bit of water and sunlight – will pretty much cover the basic needs of this plant.

How to Grow a Pencil Cactus or Milk Bush Plant

One of the best features of the milk bush plant is how easy it is to grow and keep. It is an extremely low maintenance plant, barely even requiring watering.

The pencil cactus plant can be started by simply rooting a clipping in water. Once the plant gets some roots, transfer it into a pot that will accommodate its future size. This plant grows fairly quickly and can grow as tall as 30 feet outside. Inside plants may be kept to a smaller height.

Benefits of Growing the Milk Bush

This particular plant is a very fast grower. It can grow to heights of up to 15-feet tall or more and even achieves growth of up to 10-feet or more when kept as a house plant. It is extremely resistant to drought conditions and will grow heartily on little to no water. What this plant does need, however, is space. Because of its great height, it must have adequate room on the ground – usually a few feet.

This plant can also be grown fairly easily indoors, as long as it is placed in a sunny location. It will generally not grow as tall as an outside milk bush plant, but you probably wouldn’t want it that big if you are keeping it in the house anyway. A large to extra large pot should be sufficient.


Warnings About the Pencil Cactus

On the down side, the milk bush plant is poisonous and can cause an allergic reaction ranging from mild to severe enough to require hospitalization. As with other tropical plants of this type, the stems of the milk bush plant contain a milky white sap-like substance that oozes out whenever the stem is cut or broken. The effects of this sap on humans can vary widely. Most of the time, an allergy to the sap results in redness and sensitivity in the area where contact is made. There have also been reports of serious allergic reactions, including shortness of breath, where an emergency trip to the hospital was needed.

The danger does not stop gardeners from growing the milk bush plant. It is very common in yards all over the south, especially in the desert landscapes of the southwest. A bit of caution can eliminate any problems with this plant. Whether inside or out, do not keep a milk bush plant in a high traffic area. Give it plenty of space to grow and plant it a good distance away from common areas. Always wear gloves when working with this plant, especially while trimming or taking cuttings as this is when the sap is most likely to come in contact with the skin. Finally, thoroughly wash hands with soap and water after touching the plant, even if gloves have been worn. This will prevent the sap from getting in eyes or transferring to anyone else.