Myrtillocactus: Overview of the small genus of columnar cacti

Appearance and distinguishing characteristics

Plants in this genus have thick, water-storing stems with ribs or tubercles, small areoles, and short spines. Flowers are relatively small — typically white to pale yellow — and give way to fleshy, often dark-coloured berries. The stems sometimes display a bluish or glaucous coating. Their succulent habit allows them to survive extended dry periods. Botanical details and identification notes are available via plant descriptions.

Species

• Myrtillocactus geometrizans — the best known species; widely cultivated and variable in form.
• Myrtillocactus cochal — a less common species restricted to parts of western Mexico.
• Myrtillocactus eichlamii — a rarer taxon with more localized distribution.
• Myrtillocactus schenckei — another species from the same general region.

For regional checklists and species accounts consult Mexico flora and Guatemala records.

Distribution and habitat

Myrtillocactus species are native to arid and semi-arid regions of Mexico and nearby areas of Central America. They grow on rocky slopes, scrublands and open dry forests where drainage is good and rainfall is seasonal. These habitats support pollinators and fruit-eating animals that help disperse seeds.

Uses, cultivation and importance

Several species are popular in cultivation for their architectural stems and ornamental fruit. They tolerate full sun, warm temperatures and periods of drought. Propagation is commonly by cuttings or seed. Myrtillocactus is also used as rootstock for grafting more delicate cactus species because of its vigor and resistance to certain soils. The fleshy fruits are edible and are collected locally in some areas. Practical cultivation advice and horticultural notes can be found at species care and flower and fruit resources.

Notes and distinctions

Although similar in habit to other columnar cacti, Myrtillocactus is distinguished by its combination of small flowers, berry-like fruits and particular stem morphology. Gardeners value M. geometrizans in particular for its adaptability and striking bluish stems. For additional horticultural or taxonomic information see further reading.