Sclerocactus range in shape from ovoid to elongate cylindric, have rigid stems with tubercles that are generally coalesced into ribs, and are covered with spines that come out of the areoles.

A large percentage of plants in habitat show signs of water debris damage along the stems which has healed and are found growing on their sides in places where floodwaters have deposited them.

They are tolerant of overwatering provided they are grown in small pots that drain and dry out quickly.

Like Pediocactus, Sclerocactus "deflate" in late fall in preparation for winter and freezing; they push water out of the plant flesh, through the roots, and into the soil, dramatically decreasing in size.

Some species, such as S. parviflorus, produce large, showy flowers and put a short, but impressive floral display in early spring.

Seeds of members of this genus can take up to three years to germinate in some cases if not scarified or subjected to repeated freeze-thaw cycles in the presence of water.