Pencil tree / Milk bush

Euphorbia tirucalli, the pencil tree or milk bush, is a shrub or small tree in the spurge family, known in Japan as midori-sango or ao-sango. It is thought to be native from eastern and southern Africa to Madagascar, but long planting as hedging has naturalised it so widely that its true origin is unclear; it is also established across tropical Asia, including India. In the wild it reaches 5–9 m, with much-branched cylindrical, spineless succulent twigs about 7 mm thick. Small leaves 1–2.5 cm long on young shoots fall early, leaving just the green stems. The small yellow-green flowers at the branch tips are inconspicuous. Cut stems bleed white latex, the source of the name 'milk bush'; it is strongly irritating to skin and mucous membranes and can cause temporary blindness if it reaches the eyes, so handle the plant with great care. Its hydrocarbon-rich latex was once studied as a fuel source. Forms with red-tinged stems are also sold. In pots it stays at about 60 cm–1.8 m and can be grown in a bright room. Japanese references class it as a summer grower; it is cold-sensitive and should be kept indoors in winter. It is widely sold as a staple in houseplant and succulent sections in Japan.

Source: Wikipedia (CC BY-SA 4.0)

The Pencil tree / Milk bush grows to 5–9 m in the wild (60 cm–1.8 m in pots).

Light feeder; avoid very rich soil