Mirtillocactus geometrizans (Mart.) Cons. ("crested" specimen)

Description

The botanist Michelangelo Console, of Palermo, created the name of the genus with reference to the similarity of its fruits to those of the bilberry, Vaccinium myrtillus. In the wild it takes the form of a tree more than 4 metres tall, heavily branched right from the base. The trunk and branches, blue-green in colour and strongly glaucous because of the bloom that covers them in their young parts, have 5-6 very rounded ribs with large areoles from which small black spines emerge. The flowers are whitish and are produced at the beginning of summer. The fruits, small bluish-black berries 1-2 cm in diameter, are edible both fresh and dried, like grapes, and are called “garambullos” by the local people. The entry shows a splendid “crested” specimen. Sometimes, for reasons not yet well established, the growth of the plant does not follow the vegetative axis but develops in a fan shape on one plane. This growth anomaly, called “fasciation” or “cresting” and fairly typical of succulent plants, gives Mirtillocactus geometrizans an unusual and fascinating appearance: a true plant sculpture. These specimens, not very common, are highly sought after by collectors willing to pay high prices to own one.

Cultivation

In gardens one commonly finds normal young specimens reproduced from seed. Crested plants are reproduced from branch cuttings taken from old mother plants. It even seems that they all originated from a single crested plant in the collection of a nurseryman on the French Riviera. Exposure to full sun encourages the glaucous colouring of the stem, and the plant also appreciates a fairly rich soil. Attention must be paid to minimum winter temperatures: if they are below 10 degrees the plant does not die, but its epidermis is irreparably disfigured by dark spots which, in time, turn corky. Mirtillocactus geometrizans is a vigorous grower, and precisely because of this characteristic young plants grown from seed or rooted branch cuttings are used as rootstocks for other cacti.

Propagation

Grown from seeds or scions of branches.