Synonyms:

Copiapoa chaniaralensis
Copiapoa humilis subsp. taltalensis
Copiapoa humilis subsp. variispinata
Copiapoa paposoensis
Copiapoa taltalensis
Copiapoa variispinata
Echinocactus humilis
Echinocactus taltalensis

Habitat:

Copiapoa humilis subs. tenuissima is native to Northern Chile, where it grows on coastal deserts in steep slopes, among the rocks, in poor, mineral soils. This habitat is almost rainless, and the cacti gets the water it needs from the frequent coastal fogs. It is capable of an extremely efficient water utilization thanks to its thick root.

Description:

Copiapoa humilis subsp. tenuissima, also called Copiapoa tenuissima, is a globose cacti that tends to branch at the base of the stem, creating low clusters. The colour of the stem is olive green, dark, with some violet tinges, almost black. Stems are slightly flattened to sphaerical and have a diameter of 2 to 5 centimeters and their surface is slightly warty. It has 13 to 16 ribs, defined by tubercles and usually arranged in spirals. At the top of the tubercles we find the areoles, which are white, slightly woolly and fluffy, and give birth to short, thin greyish-white spines that become black as they age. Spines are arranged in 8 to 14 radial ones, which are 3-6 millimeters long, yellowish to black, and fall off the stem after a while, and up to 2 central ones, sometimes absent,up to 1 centimeter long.
Flowers are one of the most appreciated features of this species. They are though quite small (up to 3 centimeters long and less than 1 centimeter wide). They are diurnal, bright yellow, sweet-scented, and they appear at the top of the plant in Spring and Summer. Fruits are globose, brownish-green and slightly woolly.
Roots are instead tuberous, stout and large, attached to the stem by a slender part. Compared to the stem, roots are huge; they can be up to 6 times bigger than the above-soil parts of the plant.

Cultivation:

Copiapoa humilis subsp. tenuissima is not difficult to grow, though it’s definitely a slow-growe. Here below are our cultivation tips:

Put it in a bright spot, but not exposed to sunlight all the time: the hottest hours of the day should be avoided. Best options are early morning and late afternoon sunlight.
In theory, it can survive at temperatures down to -5ºC. In cultivation conditions, however, we advise to keep it at minimum temperatures of 5ºC. You might put it Duriing the cold season, keep its substrate completely dry and avoid atmospheric humidity: try to keep it in airy spots.
Water weekly during the Summer, always waiting that for the soil to dry up completely before each irrigation. In Spring and Autumn, water unfrequently but abundantly, whenever the substrate is copletely dry. In Winter, instead, any irrigation should be avoided.
Choose a well-drained soil, with an abundant mineral part.
Fertilize once a year during the growth season, with a specific product for cacti and succulents (high in Potassium and Phosphorus and poor in Nitrogen), diluting it in water at half the doses recommended on the label.
Repotting is rarely necessary as it stays very small. Choose deep pots to host it big root system. 

Propagation:

The propagation of Copiapoa humilis subsp. tenuissima is usually carried out through seeds or cuttings. It’s also frequent to find plants grafted on more tough individuals, to enhance growth speed. Cuttings can instead be taken off the shoot in Spring and Summer, to be planted in cactus potting mix after the wound has dried up (a callous should form). Keep the substrate with the planted cuttings moist and at temperatures above 20ºC until they put roots. Seeds, instead, germinate in around a week at 20 to 27ºC in Spring. Put a glass or plastic sheet above the pot and remove it gradually after the plantlets start to germinate.

Curiosity:

Its name derives from Greek and literally means “with the appearance of a snake”, referring to its stems which, in most species, with growth tend to crawl on the ground.

Official Web Site:
www.giromagi.com

Italian Blog:
www.giromagicactus.com

Tips:
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