Origin
The Mammillaria hahniana, also known as the Old Lady Cactus, is a cactus species native to Mexico. It is particularly found in the Mexican states of Guanajuato, Hidalgo, and Querétaro. The species mainly grows in subtropical or tropical dry forests and on dry, rocky slopes.

Characteristics
The Mammillaria hahniana is characterised by its round, globular growth. Unique are the woolly parts at the top and its spines which vary from white to silvery grey to brown. In the growing season, the plant produces small, pink-red flowers around its top, creating a striking contrast with its spiky appearance. Its growth is relatively slow, with mature plants usually not taller than 6 centimetres.

Care
In caring for the Mammillaria hahniana, its need for well-draining soil and a sunny placement must be considered. Over-watering should be avoided, as the plant is relatively drought tolerant and prone to root rot if too wet. In the winter months, it is advisable to reduce the water provision and keep the plant in a cooler, bright place. It is susceptible to frost and temperatures below -1 degrees Celsius should therefore be avoided.