Columnar cacti are not a closely related set of genera, but a lumping together of all the cacti that are much longer than they are around.

A small (but growing) genus of small plants from Northeastern and Central Mexico.

This month both the Cactus and Succulent categories are Variegates.

Three cactus genera that are not so common in collections.

Two similar genera from Peru.

Genera from the highlands of Bolivia and Northern Argentina.

Any container will be accepted, but cactus dish gardens must be 100% cactus.

Spectacularly beautiful cacti with dense multicolor spination, from Southern USA and Mexico.

Stenocactus is a genus of northern and central Mexican cacti of around 10 species related to Ferocactus.

Mammillaria is one of the larger genera in the Cactus family, and one of the most variable.