Mammillaria carretii

Mammillaria carretii is not particularly common in cultivation, despite been known to collectors for over 100 years. It is an interesting plant with larger that average Mammillaria flowers and long hooked centrals, readily clumping. Native to Nuevo Leon state of Mexico plant grows well in pure mineral substrate. With watering it better be kept on a dry side - to me that means good draining every 10 days or two weeks, letting pot to dry completely before watering.