(This plant comes in a 3.5 inch 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).
Flowers: white to pale pink, 3.5 to 6 cm long.
Flowering time: Blooms appear recurrently from June to autumn. It flowers quite readily as a young seedling.
Cultivation and Propagation: Gymnocalycium triacanthum is a summer grower species that is easy to cultivate.
Soils: It likes very porous standard cactus mix soil.
Watering: Needs moderate to copious waterings in summer, but do not overwater (Rot prone), keep dry in winter at a minimum temperature of 0°C.
Hardiness: Reputedly resistant to frost if kept on the dry side prior to, and during, cold weather (hardy to -5 C ° C, or less for short periods).
The species name "triacanthum" comes from the Greek for "with 3 spines".
Some of the information in this description has been found at desert-tropicals.com, llifle.com and cactus-art.biz