Mammillaria Ignota, commonly known as Pincushion Cactus.
Common Names: Pincushion Cactus
Height and diameter: Grows to about 15cm tall, 8cm diameter
Light: Full sun.
Water: Requires well-drained soil, and only moderate watering. The soil should be allowed to dry between watering, rather than kept perpetually damp.
Flowers: Produces small magenta flowers in autumn.
Propagation: By removing and replanting offsets.
Care: Very low-maintenance plant in suitable growing conditions. Keep in well-draining soil, and protect from frosty conditions.