(This plant comes in a 3.5" pot. You will receive a very similar plant to the one in the picture. It may or may not be blooming at the time of your purchase. The plant is shipped in its pot to prevent any damage to the roots).
This is an extremely slow growing and one of the nicest Gymnocalyciums species. It has incredibly strong curved spines. If you only have one Gymnocalycium, this is the one to have!
Description: Solitary, slowly growing cactus, densely covered with incredibly strong twisted spines
Blooming season: They will bloom at an early age and bloom sparingly in mid-summer.
Cultivation: Keep this plant almost dry in winter at a minimum temperature of 0°C. It prefers a low pH compost; otherwise growth will stop altogether. The plant tolerates extremely bright situations.
Recommended Temperature zone: USDA: 9-11
Frost Tolerance: 20°F (-7°C)
Minimum Avg. Temperature: 50°F (10°C)
Sun Exposure: Light shade to full sun
Origin: Bolivia (Tarija)
Growth Habits: Solitary, globular, slowly growing up to 5"(12 cm)
Watering Needs: Summer grower, water regularly in summer, keep rather dry in winter
Some of the information in this description has been found at desert-tropicals.com, llifle.com and cactus-art.biz