Gymnocalycium baldianum (Dwarf Chin Cactus) is a small cactus with usually solitary, spherical or a little flat stem with 9 to 10 broad…
Origin and Habitat: Argentina, Catamarca Province (Sierra Ancasti, Sierra Graciana, Sierra de Narvaes, Sierra de Guayamba, Sierra de Manchao and on the mountains east of Andalgalá)
Altitude: It grows at elevations of 500 to 2000 metres above sea level.
Habitat and Ecology: This high-altitude plant is often found among grass. Gymnocalycium baldianum has a relatively restricted range, has a continuous distribution and is not fragmented. Collection is a major threat for the species in parts of it range also fire affects it in some areas.
Description: Gymnocalycium baldianum small usually unbranched.
Stem: Flat to globose depressed, up to 13 cm in width, greyish-brown to blue-green (rather variable in colour in cultivation, and in some specimens it is almost blue-black). The 9 to 10 broad ribs are divided by deep grooves into tubercles.
Spines: 5 to 7 thin radial spines that are straight or curved toward the stem, short, curved, pale brown or grey, tinged with red at the base.
Flowers: on the crown, measuring 3 to 4 cm in length and the same across, open wide in sunlight, and commonly of a most rich purple-red colour, sometimes pinkish-purple (but also white, pink or orange). The stamens are purple, the anthers and the 6 lobed stigma whitish yellow. This plant blooms in early summer when it is only 2.5 cm. It is fast growing and can bloom one year after being sown.
Fruits: The ripened ovary is green, long and dehisces (splits) down its length.
Remarks: The synonym name Gymnocalycium venturianum is very common in collections, and even at cactus nurseries. It is a very variable species in its general appearance. There are also many hybrids with a wide range of flower colours.
Subspecies, varieties, forms and cultivars of plants belonging to the Gymnocalycium baldianum group
Notes: It is one of the hybridparent of: Gymnocalycium × pazoutianum Halda Acta Mus. Richnov., Sect. Nat. 5(4): 164 (1998).
Bibliography: Major references and further lectures
1) Edward F. Anderson “The Cactus Family” Timber Press, 2001
2) Curt Backeberg “Cactus Lexicon” Sterling Publishing Company, Incorporated, 1978
3) David Hunt, Nigel Taylor “The New Cactus Lexicon” DH Books, 2006
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/Aug./2011
5) Perea, M. & Trevisson, M. 2013. Gymnocalycium baldianum. In: IUCN 2013. "IUCN Red List of Threatened Species." Version 2013.2. . Downloaded on 25 February 2014.
Cultivation and Propagation: Gymnocalycium baldianum is very easy to grow, these plants offer no cultivation difficulties.
Watering Needs: Moderate to copious in summer, keep dry in winter.
Frost Tolerance: Quite frost resistant if kept dry -10° C (Temperature Zone: USDA 8-10 )
Cultural Practices: Feed with a high potassium fertilizer in summer.
Sun Exposure: Full sun to light shade.
Propagation: Seeds (seldom produces offsets).
It is a globose cactus, spherical or a little flat, with a diameter up to 8 cm, dark green in colour, or sometimes brown. It has 8 to 10 ribs with tubercle-shaped areoles, covered in groups of 6 to 8 pale grey, curved spines, giving to the species its common name of spider-cactus. Like many cacti, it does not divide but may form offsets after some years. The funnel-shaped flowers reach a diameter of 6 cm, growing near the apex of the plant and are red, pink or orange. 
|Family:||Cactaceae (kak-TAY-see-ee) (Info)|
|Genus:||Gymnocalycium (jim-no-kal-LISS-ee-um) (Info)|
|Species:||baldianum (bald-ee-AY-num) (Info)|
|Synonym:||Gymnocalycium platense var. baldianum|
Drought-tolerant suitable for xeriscaping
USDA Zone 8b: to -9.4 °C (15 °F)
USDA Zone 9a: to -6.6 °C (20 °F)
USDA Zone 9b: to -3.8 °C (25 °F)
USDA Zone 10a: to -1.1 °C (30 °F)
USDA Zone 10b: to 1.7 °C (35 °F)
USDA Zone 11: above 4.5 °C (40 °F)
Can be grown as an annual
Plant has spines or sharp edges use extreme caution when handling
By dividing rhizomes, tubers, corms or bulbs (including offsets)
Allow cut surface to callous over before planting
From seed direct sow after last frost
Allow unblemished fruit to ripen clean and dry seeds
Unblemished fruit must be significantly overripe before harvesting seed clean and dry seeds
This plant is said to grow outdoors in the following regions:
On Sep 16, 2019, 2QandLearn from Menifee, CA (Zone 9a) wrote:
I was just browsing pictures to help me discover the ID of a cactus I've had for about 15 yrs, when I discovered its name is this one @ [ [email protected] ] . . . It's been flowering every year since I bought it, with beautiful bright red flowers! I think it's as big as it's ever going to get. . . . Had been wondering how much it might grow if in a bigger pot.
On Apr 13, 2015, Max64 from Las Vegas, NV (Zone 9a) wrote:
I love the Chin cactus. I have 3 and every time I see one at the nursery I immediately take it home. The blooms are a gorgeous red and mine bloom from spring to fall. One has more of a pink red bloom. I do water them frequently during the hot Vegas summer. They are planted a few feet away from my Mediterranean fan palm and enjoy the filtered light from the fronds in the afternoon sun.
On Feb 20, 2005, palmbob from Acton, CA (Zone 8b) wrote:
Small globoid sparsely spined green cactus with impressive large flowers of a variety of color possibilities. Spines that are present are stiff, but tend to lie flat against the body of the plant so plant is 'user friendlly'. Though a small cactus, grows fast up to maximum size and supposedly can flowers one year from seed.