Habits: Normally clumping, up to 5 feet tall (1.5 m), stems up to 10 inches in diameter (25 cm), branching laterally, this is the largest of the Copiapoa genus. It has 14 to 22 ribs; spines 1.2 inches long (3 cm); 0 to 2 central spines; 0 to 8 radial spines. The young plants are green and do not attain their delightful and distinctive grey epidermis until they are several years old. The grey colour is caused by a strong layer of crystallised wax, which prevents excessive evaporation of water. The crown of the plant is covered in creamy yellow wool.
Scientific name: Copiapoa hasteltoniana
Common names: Not known.
Synonym: Copiapoa cinerea var. gigantea, Copiapoa tenebrosa, Copiapoa eremophila, Copiapoa cinerea ssp. haseltoniana, Copiapoa gigantea var. haseltoniana
Etymology: Named after the town of Copiapoa, in Chile. Haseltonia is named in honor of Scott E. Haselton, first editor of the journal of The Cactus and Succulent Society of America (CSSA)
Origin: Chile (Antofagasta: Paposo). Chile has a coastline over 2,700 miles long, but the average width of the country is less than 125 miles. Thus the climate of the country is strongly influenced by the Pacific Ocean. The north of the country extends into the tropics and the south around the 56th parallel is in the cold zone. Some species of cacti in Chile grow in some of the driest places on the planet. Areas of the Atacama desert virtually never see any rain and the cacti here have to get their moisture from the heavy mists that sometimes occur.
Light: The plant is fairly accommodating and will take full sun to light shade.
Compost: The compost can be fairly nutritious, but should still be very free draining. You all have your favourites, I know. With this plant a little more grit or perlite may be advantageous and a calcareous compost is also appreciated by the plant.
Water: They should be watered with some care and if they have attained a clump, care should be taken to ensure that water does not become trapped between the plant bodies.
Flower: The flower of the plant is a golden yellow and the blooms appear from late summer to early autumn. However it takes a tremendous amount of patience to wait for a flowering specimen and most enthusiasts will probably never see a flower on their own plant[s].
Fruit: No information
Min. temp: Prefers a slightly higher temperature than many cacti need during the winter. It should not be subjected to temperatures lower than 50°F (10°C)
Cultivation: The plant does not ask for a great deal apart from a nice sunny spot, but be careful not to put it where there is a lot of heat build-up (there is a difference). Not too heavy handed with the watering can and everything should be fine. The plant should be kept fairly dry in winter and in colder climates brr . . . (England) do not water at all, unless it is in a very warm room where a little once a month will stop the plant from shrivelling.
Habitat: The plants native habitat is slowly being destroyed by the influence of man. The main area of the plant population is found to the south of Paposo, but it disappears near the village and then occurs again to the north. The plant grows at altitudes between 300-1500ft.
Comments: I suppose to cacti hobbyists 99% of cacti are beautiful, even if you do not want a particular plant in your own collection. This is among the most distinctive of cacti and in my humble opinion one of the most beautiful. The plant is currently accepted as a subspecies of Copiapoa cinerea in the New Cactus Lexicon 2006.