Origin and Habitat: Sierra Hornillos, South of Copiapò. It is the southern population of C. humilis found at about 350 km from the growing area of the type species. There are not intermediate populations and no hybrids are found between the two sorts.
Habitat: It grows in an area where constantly sunny weather prevails, together with a great aridity. However this southern region benefits of some winter rain.

• Copiapoa humilis var. longispina (F.Ritter) A.E.Hoffm.
• Copiapoa humilis subs. longispina (F.Ritter) Doweld
• Copiapoa longispina F.Ritter

• Copiapoa humilis (Phil.) Hutchison
• Echinocactus humilis Phil.
• Copiapoa humilis subs. australis Hoxey
• Copiapoa humilis f. cristata hort.
• Copiapoa maritima Kníže
• Copiapoa paposoensis F.Ritter
• Copiapoa humilis var. paposoensis (F.Ritter) A.E.Hoffm.

• Copiapoa humilis var. longispina (F.Ritter) A.E.Hoffm.
• Copiapoa humilis subs. longispina (F.Ritter) Doweld
• Copiapoa longispina F.Ritter

• Copiapoa humilis subs. tenuissima (F.Ritter ex D.R.Hunt) D.R.Hunt
• Copiapoa humilis var. tenuissima (F.Ritter) G.J.Charles
• Copiapoa hypogaea subs. tenuissima F.Ritter ex D.R.Hunt
• Copiapoa tenuissima (F.Ritter ex D.R.Hunt) D.R.Hunt
• Copiapoa humilis subs. tenuissima f. cristata hort.
• Copiapoa tenuissima f. cristata hort.
• Copiapoa humilis subs. tenuissima f. monstruosa cristata hort.
• Copiapoa tenuissima f. monstruosa cristata hort.
• Copiapoa humilis subs. tenuissima f. monstruosa hort.
• Copiapoa tenuissima f. monstruosa hort.

• Copiapoa humilis var. tocopillana (F.Ritter) G.J.Charles
• Copiapoa humilis subs. tocopillana (F.Ritter) D.R.Hunt
• Copiapoa tocopillana F.Ritter

• Copiapoa humilis subs. variispinata (F.Ritter) D.R.Hunt
• Copiapoa humilis var. variispinata (F.Ritter) G.J.Charles
• Copiapoa variispinata F.Ritter

Description: Solitary, rarely offsetting of its own. It seems likely that many of the forms described as species can be regarded under humilis, as subspecies or as forms and now some authors considers C. humilis ssp. longispina (Ritter) Doweld as C. humilis ssp. humilis (Philippi) Hutchison.
Stem: Hemispherical, lighter green (usually) to dark green (occasionally almost black) about 10 cm in diameter, covered with greyish wax. It is usually less caespitose than the type. The stem is also harder than that of the Copiapoa humilisSN|9790]]SN|9790]]. The crown is somewhat depressed, with white woolly felt.
Root: Massive, thickened rootstock going well down into the ground, with a long narrow neck.
Ribs: About 8-14 forming distinct tubercles.
Areoles: Well separated, with white wool.
Central spines: Stronger than the type, almost white to blackish up to 50 mm long.
Radial spines: 7 to 90 finer and shorter, up to 20 mm long.
Flowers: Yellow, campanulate, scented, about 20 (or more) mm long, growing from the centre of the white wool at the apex.
Seeds: 1,5 mm wide, black.
Fruit: Round, naked, red, about 8 mm long.
Remarks: The identification of the true 'longispina' may concern a degree of uncertainty as to what this plant is, and many plants found in cultivation are Copiapoa humilisSN|9790]]SN|9790]] ssp. humilis.

Notes: C. humilis is a highly variable taxon with several more or less similar forms that could be described as local varieties.
Taylor suggests that this is a very complex species or species aggregate, perhaps representing geographical varieties or, in some cases, critical species, listed here in sequence from north to south: Copiapoa tocopillanaSN|9783]]SN|1326]], Copiapoa tenuissimaSN|9770]]SN|1138]], Copiapoa variispinataSN|1425]]SN|9776]], Copiapoa paposoensisSN|1391]]SN|9794]], Copiapoa taltalensisSN|9794]]SN|1391]], Copiapoa longispinaSN|9776]]SN|1425]] and possibly Copiapoa chaniaralensisSN|1138]]SN|9770]] and Copiapoa esmeraldanaSN|1326]]SN|9783]].
In considering C. humilis species, we need to bear in mind the remarkable differences between young plants, with short, thin spination and the darker coloration of the body compared to the more robust adults with longer and sturdy, flexible spines.

Bibliography: Major references and further lectures
1) Robert Silverberg “The Palace at Midnight: The Collected Stories, Volume 5“ Hachette UK, 29/Sep/2011
2) Graham Charles “Copiapoa” Cirio Pub. Services, 1999
3) Riha & Subik. “The illustrated encyclopedia of cacti and other succulents” (edited by G. & K.A. Beckett) 1981
4) James Cullen, Sabina G. Knees, H. Suzanne Cubey “The European Garden Flora Flowering Plants: A Manual for the Identification of Plants Cultivated in Europe, Both Out-of-Doors and Under Glass” Cambridge University Press, 11/ago/2011
5) Clive Innes “Complete Handbook of Cacti and Succulents” Van Nostrand Reinhold Company, 01/Dec/1981
6) Edward Anderson “The Cactus family” Timber Press, Incorporated, 2001
7) David R Hunt; Nigel P Taylor; Graham Charles; International Cactaceae Systematics Group. "The New Cactus Lexicon" dh books, 2006
8) N. L. Britton, J. N. Rose “The Cactaceae. Descriptions and Illustrations of Plants of the Cactus Family.” Volume 4, The Carnegie Institution of Washington, Washington 1923
9) F.Ritter “Kakteen Südamerika” 3: 1072 1980

Cultivation and Propagation: Considering that Copiapoa humilis var. longispinaSN|1427]]SN|1427]] comes from a habitat with an extremely arid climate, they are remarkably tolerant of pot culture. These plants have thick taproots and are susceptible to overwatering. They requires also an appropriate air circulation. Copiapoas are summer grower species easy to cultivate
Growth rate: It is a relatively rapidly growing and easily flowering species that will make clumps given the best conditions.
Soils: It likes very coarse mineral cactus mix soil, but can become too elongated if compost is too rich.
Repotting: Use pot with good drainage.
Watering: Water moderately from Spring to Autumn, but do not overwater (Rot prone), it must be strictly kept dry throughout the winter quiescent period since it is very sensitive to any moisture excesses keep dry in winter.
Fertilization: Feed with a high potassium fertilizer in summer.
Hardiness: They need to be kept in a cool place during winter rest and are resistant to light frost if kept on the dry side prior to, and during, cold weather ( they are hardy to -4 C ° C short periods). However some warmth throughout the year will increase the grower's success (minimum 5° to 8°C during rest season).
Exposition: Requires full sun or light shade and careful watering to keep plant compact with strong coloured spines. Tends to bronze in strong light, which encourages flowering and heavy spine production. Light shadow my be useful in the hottest summer days.
Uses: It is an excellent plant for container growing. It always looks good and stays small. It look fine in a cold greenhouse and frame or outdoor in a rockery.
Pests & diseases: It may be attractive to a variety of insects, but plants in good condition should be nearly pest-free, particularly if they are grown in a mineral potting-mix, with good exposure and ventilation. Nonetheless, there are several pests to watch for:
- Red spiders: Red spiders may be effectively rubbed up by watering the infested plants from above.
- Mealy bugs: Mealy bugs occasionally develop aerial into the new growth among the wool with disfiguring results, but the worst types develop underground on the roots and are invisible except by their effects.
- Sciara Flies: Sciara flies are one of the major problems for seedlings. It is a good practice to mulch your seedlings with a layer of grit, which will strongly discourage the flies.
- Scales: Scales are rarely a problem. It is wise to treat your whole collection with a systemic insecticide twice a year in spring and autumn.
- Rot: Rot is only a minor problem with cacti if the plants are watered and “aired” correctly. If they are not, fungicides won't help all that much. To prevent rottenness it is also advisable to surround its root neck by very rough sand or grit, this help a fast water drainage.
Propagation: Seed, cutting, grafting. Seeds germinate in 7-14 days at 21-27° C in spring, remove gradually the glass cover as soon the plants will be well rooted (ca 1-2 weeks) and keep ventilated, no full sun for young plants!