Ortegocactus (2010)

By Eric Driskill (January 2010)

The Cactaceae family includes the monotypic genus Ortegocactus, whose only species is O. macdougallii. This oddity from Mexico is poorly understood. Some believe it is a link between Mammillaria and Coryphantha.

This plant was discovered in the winter of 1951-1952 by Tom MacDougall. Its name honors the Ortega family of San Jose Lachiguiri, who assisted MacDougall. O. macdougallii is found only in Oaxaca in an escarped limestone area practically devoid of trees and scrubs, at a height of 6,560 feet.

The plants have a very distinctive bluish-green color like no other. Look up a photo in any book or website and know that it doesn’t do justice to the real color. The single central spine is almost half the size of the seven or eight, 0.2- to 0.4-inch radial spines. All spines are black or whitish with black tips. Their dark color is a stark contrast to the color of the plant body. Stems are 1 inch wide and in time form a cluster. Bright yellow flowers are produced in the spring from the tips of the stems.

O. macdougallii is a small plant which doesn’t take up much bench space, and the color of the plant is always a conversation piece. O. macdougallii does pose its challenges in growing on its own roots to a specimen cluster of healthy stems.

The plants tend to get an orange-brown or reddish discoloration starting at the base of the stems which can eventually engulf the entire plant. Bright light and good air circulation can help prevent this discoloration.

Plants are also prone to rot. A shallow pan with coarse compost is suggested, with a layer of gravel, grit or diatomaceous earth as top dressing to provide air to the stem.

Although no longer as rare in cultivation as it once was, it is still a plant you don’t find at every sale or nursery. If you want to add a unique plant to your collection which can be a challenge to grow, you can consider O. macdougallii without too much strain on the pocketbook. When you see a nicely grown plant in a show or in someone’s collection, take time to ask questions about the owner’s cultivation approach – and take good notes.