Myrtillocactus (2010)

By Eric Driskill (October 2010)

The genus Myrtillocactus was first described by Karl Martius as Cereus geometrizans in 1837. In 1897, Myrtillocactus was described by Michelangelo Console. The name is derived from the Greek “myrtillo,” meaning small, myrtlelike, referring to the fruits, which resemble those of the true myrtle, Myrtus communis.

There are four species of recognized Myrtillocactus. The plants grow from as far south as Guatemala to Oaxaca in southern central Mexico, north into northern Mexico, including Baja California.

Myrtillocacti are unusual in that more than one flower is produced from each of their areoles. The size of the blooms is also unusually small for plants as large as these. The flowers are a greenish-white color, waxy and somewhat translucent. They later give rise to blue fruits, which are very tasty and have been used by native people for centuries. The fruit is often sold in markets under the common name “garambullo.”

The plants are all similar in that they are treelike, branching plants with four to eight prominent ribs. Typically the ribs features a single, thick, long central spine and only a few thick, short radial spines, or the areoles may be spineless.

Although plants in habitat are columnar, candelabralike tree cacti, you will unlikely have a potted plant that gets large enough to flower. However, it is quite possible that you have an M. geometrizans in your collection and don’t even know it yet. This plant is commonly used as grafting stock.