Cephalocereus senilis – Old man's head

There's no doubt about it: the abundant white wool covering this tall cactus certainly resembles an old man's hair or beard. Cephalocereus senilis belongs to the Cactaceae family. It is native to the steep slopes of central-eastern Mexico, in the states of Guanajuato, Veracruz, and Hidalgo.

How can you recognize Cephalocereus senilis, the “old man's head” cactus?

Cephalocereus senilis is a columnar cactus. Unlike Cereus forbesii, it is generally unbranched. In its natural habitat, it can reach heights of ten to fifteen meters and a base diameter of nearly 45 centimeters… when it's a century old! So rest assured, your little spiny old-timer won't grow to such gigantic proportions, whether it's grown indoors or outdoors in the mild climate of the French Riviera.

Its grayish-green stem bears yellowish spines—one to five per areole—and numerous white hairs, 6 to 12 centimeters long. This white “hair” is particularly abundant at the top of the stem. This characteristic stems from the cactus's adaptation to its mountainous environment. The thick down protects it from the intense heat of the sun's rays during the day, as well as from temperatures near 0 °C on winter nights.

The old man's head cactus blooms at its top, usually after 10 to 20 years. Flowering occurs at night during the summer, producing red, yellow, or white flowers with pale pink hues. In the deep Mexican barrancos (gorges), they are pollinated by nectar-feeding bats.

Cephalocereus senilis is not known to be toxic to pets or humans. But that doesn't mean you should go petting its attractive fuzz: the “old man cactus” hides sharp spines in its beard!

Diseases / Threats