Schedule Change

On Friday, September 19, the U.S. Botanic Garden's outdoor National Garden will close early at 5 p.m. It will reopen for regularly scheduled hours on Saturday, September 20 at 10 a.m.

Old woman cactus

Mammillaria hahniana (Old woman cactus)
Plant Botanical Name: 
Mammillaria hahniana
USBG Plant Location: 
Conservatory
Conservatory Room Location: 
World Deserts
Plant Threat Level: 
Vulnerable

Mammillaria hahniana is commonly known as the old woman cactus because of the grayish hairs that protect it from the harsh sun common to its native habitat in the Mexican state of Guanajuato. Mexico is an important center of diversity for the Cactus family, containing more than 500 species and possessing the highest number of endemic and endangered cacti of any country in the world. Though wild populations of Mammillaria hahniana are still considered vulnerable, widespread propagation of this species by commercial nurseries catering to cactus hobbyists has greatly reduced the demand for plants illegally collected from naturally occurring populations.