Origin and Habitat: Rebutia cardenasiana is endemic to Cochabamba and Chuquisaca, Bolivia. The species is present in a large area, however it is unknown how abundant it is, there might be some decline in the population however, is difficult to establish how significant this is.
Altitude range: Rebutia cardenasiana grows at at elevations of 1,800-2,800 metres above sea level.
Habitat and Ecology: This species grows in seasonally dry inter-Andean valleys on sandstone outcrops. Part of the species range is affected by agriculture.

• Rebutia cardenasiana (R.Vásquez) G.Navarro
• Sulcorebutia cardenasiana R.Vásquez
• Weingartia cardenasiana (R.Vásquez) F.H.Brandt

• Rebutia cardenasiana (R.Vásquez) G.Navarro
• Sulcorebutia cardenasiana R.Vásquez
• Weingartia cardenasiana (R.Vásquez) F.H.Brandt
• Sulcorebutia langeri K.Augustin & Hentzschel
• Weingartia langeri (K.Augustin & Hentzschel) Hentzschel & K.Augustin
• Sulcorebutia langeri G245/5 km 10, Valle Grande to Mataral, Santa Cruz, Bolivia

Description: Rebutia cardenasiana (firstly described as Sulcorebutia cardenasiana by R. Vásquez in 1975) is a beautiful yellow-flowered Sulco from Bolivia. It is a cute globular cactus with short pectinate spines related to Rebutia steinbachii, but sufficiently differentiated and considered a good species on its own.
Stems. Solitary, globose, dark green, to 5 cm high and 8 cm in diameter.
Ribs: 14, spiraling, tuberculate.
Areoles: Yellowish white.
Central spine: One, often absent.
Radial spines: Pectinate, white, yellowish or brownish 5-10 mm long.
Flowers: Yellow (rarely orange or white), 2.5 cm long and in diameter.
Fruits: Globose, green.

Bibliography: Major references and further lectures
1) Lowry, M. 2013. Rebutia cardenasiana. The IUCN Red List of Threatened Species. Version 2015.2. <www.iucnredlist.org>. Downloaded on 25 July 2015.
2) 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
3) David Hunt, Nigel Taylor “The New Cactus Lexicon” DH Books, 2006
4) Edward F. Anderson “The Cactus Family” Timber Press, 2001
5) John Pilbeam “Sulcorebutia and Weingartia: A Collector's Guide” Timber Press, 1985

Cultivation and Propagation: This species loves a very permeable, coarse mineral soil as well as to be strictly kept dry throughout the winter quiescent period since it is very sensitive to any moisture excesses. To prevent rottenness it is also advisable to surround its root neck by very rough sand or grit, this help a fast water drainage and an appropriate air circulation. Plants are quite frost hardy -5 (-10)° C.
Watering Needs: Water moderately in the growing season, keep dry during the winter rest
Frost Tolerance: Overwinter in a cool place (at 0/10°C) this is important for the flowers as well as for plants health. Without this cool winter period they normally wont get any buds.
Sun Exposure: Needs a full sun exposure (light shadow my be useful in the hottest summer days)
Propagation: Seed, cutting, grafting.