Pencil cactus is easy to grow if three things are provided: high light, low water, and gritty soil. This plant is perfect for travelers or people who sometimes forget they have houseplants.

This plant will not tolerate low light conditions. Direct sun, or plenty of bright ambient light from a western, eastern, or southern facing window is ideal for this plant to thrive.

Euphorbia tirucalli (commonly known as aveloz, Indian tree spurge, naked lady, pencil tree, pencil cactus, milk bush  is a tree that grows in semi-arid tropical climates. A hydrocarbon plant, it produces a poisonous latex that can cause temporary blindness.

The pencil tree is a shrub or small tree with pencil-thick, green, smooth, succulent branches that reaches heights of growth of up to 7 meters.

It has a cylindrical and fleshy stem with fragile succulent twigs that are 7 mm thick, often produced in whorls, longitudinally, finely striated. The oval leaves are 1 to 2.5 cm long and about 3 to 4 mm wide; they usually fall off early. It contains a milky, toxic and corrosive sap. The yellow flowers are at the ends of the branches.