Members of the Crassulaceae are succulent herbs or shrubs that have leaves that are simple, entire, fleshy, and whorled or almost so. In many species, these leaves can be used to start new plants—and do so in the wild. 

The flowers are radially symmetric, with an equal number of sepals and petals. There are usually 5 of each, but there is quite a bit of variation. The sepals are distinct to connate, as are the petals, sometimes forming a distinctly tubular corolla.  

There are 1 or 2 whorls of stamens, the number in each whorl equaling the number of petals. The ovary is superior, and the 4-5 carpels are almost free, being united only at the base in some species. Each carpel is subtended by a nectary and contains lots of ovules on what are, in essence, axile placentae. At maturity, the carpels mature into follicles.

The Crassulaceae grows from tropical to boreal regions, often in arid habitats. Many of the boreal species grow among rocks, which warm up rapidly and reflect the sun's heat onto the plants.  

Kalanchoe fedtschenkoi

Kalanchoe fedtschenkoi

Sedum rhodanthum

Sedum lanceolatum

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