Astrophytum senile is a variety of Astrophytum capricorne, differing in its larger stems, which generally lack hair-flecks, and so densely wrapped with soft spines that the body is hardly visible, and looks like a dry grass bundle.
Stem is spherical to short cylindrical, up to 15 cm in diameter, epidermis dark green, almost naked or covered with with very few white hair-tufts.
Flowers are very showy, 6-10 cm in diameter, yellow (sometime orange or pink) with a red centre.
Like most cacti they're drought tolerant and need very little care and attention to grow well. Not enough sunlight and over-watering are common mistakes.
Plenty of sunshine will keep this cacti more than happy. In a glass room you may have to provide some shade during a hot summers day to prevent sunburn
Feed every 4 weeks with a Nitrogen-poor and Potassium & Phosphorus-rich fertilizer during summer
It is an excellent plant for garden rockery settings, desert type landscapes, patios and botanical gardens