The most familiar hens and chicks are in the genus Sempervivum. I’d like to introduce you to the less familiar with same common name which are classified in the genera Jovibarba, Orostachys and Rosularia. All are members of the Crassulacea family.
Like Sempervivum, all are monocarpic, which means when the main rosette erupts into flower, it will set seed and cease to exist. (You can see why it is a good thing that many offsets of new plantlets have been freely produced.)
The genus Jovibarba is sometimes classified as a sub genus of Sempervivum. Jovibarba is distinguished by blossoms bearing pale green to yellow 6 petaled flowers compared to Sempervivum’s 10-12 petaled pink blossoms. There are only 3 species in the genus: globifera, hueffeli and hirta. J. globifera and hirta freely produce stoloniferous offsets but J. heuffelii’s “chicks” are tightly attached to the crown, and need to be severed to propagate more babies. J. hirta ssp arenaria forms dozens of delightful miniature rosettes (1/4-3/4”) of pale gray green leaves covered with tiny hairs. Cool temperatures bring out red foliage highlights. Grow in a lean soil with sharp drainage in hardiness zones 5-9.
Orostochys is a slightly bigger genus…it includes the more popular O. iwarenge (Dunce caps) as well as several others that are garden worthy subjects. The mature rosette of O. spinosus gives the appearance of a silver sunflower with an array of silver quilled foliage surrounding a center of congested tiny tight leaves. It is hardy to zone 4-9, but requires very well drained soil. O. minutum (also listed as O. spinosum minutum) is quite petite as the specific name suggests, producing clusters of 1/2-1” rosettes of blue gray foliage. It would make an excellent alpine trough plant.
The genus Rosularia includes about 35 species. We have grown R. muratdaghensis, R. serpentinica, and R. chrysantha. Both R. muratdaghenis and serpentinica form tight mounding rosettes of gray green foliage, accented with red tones in cooler temperatures. R. chrysantha has a mat forming habit,with rosettes of soft velvety green leaves. All 3 species demand lean soil with excellent drainage and are are hardy in zones 5-9.