Hens and chickens, or houseleeks, are a large group of evergreen succulents. Sempervivums are the most popular of the types and are native to the mountains of Europe and the Mediterranean islands. Thriving in the harsh conditions at high altitudes, these alpine plants have no trouble performing in ordinary garden situations. Hens and chickens grow in rosettes and consist of a central plant and its subsequent offsets. The plants bloom atop a succulent stem, and the flowers are reminiscent of a cactus blossom.
With 50 species as parents, Sempervivum hybrids number approximately 3,000, according to The Succulent Page website. The number of hybrids makes botanical identification difficult which can be disappointing to a collector. The foliage is yellow, gray, green, pink or red and the rosette color intensifies in spring and summer. The pink or red flowers appear in midsummer and are star-shaped with numerous petals.
Rosularia and Jovibarba
Two other types of plants, Rosularia and Jovibarba, go by the common name of hens and chickens. There are far fewer species of these groups than is the case with the sempervivums. According to Fernwood Nursery in Britain, the Jovibarba species have stronger foliage texture and the rosettes hold their shape better than the sempervivums. The colors have richer tones as well. The flowers of both types are usually pale yellow with six to eight petals.
Culture and Care
Hens and chickens have simple requirements: a well-drained soil with grit added and a location in full sun. They rarely need additional water. Rosularia and jovibarba are often grown in cold frames for protection. Fertilize hens and chicks lightly with a slow-release fertilizer.
Add new soil every few years to rejuvenate the plants. Sempervivums are hardy in USDA Plant Hardiness Zones 3 to 8. Rosularia and jovibarba are hardy in USDA Plant Hardiness Zones 5 and 7.
Hens and chickens from seed flower in three years. The stem grows from the central rosette and can be up to 16 inches for some varieties. After the flower is spent, seeds form and the mother plant or "hen" dies. The offsets or "chickens" grow larger and fill in the empty area.
The offsets are attached to the main rosette by stolons, or horizontal stems. To propagate, remove an offset with developing roots from the stolon with your fingers. Place in a sterile soil medium with the addition of some grit. The roots will anchor the rosette into the soil.
The seeds germinate easily. However, the seedlings aren't true to their parents. Collect the seeds by shaking the flower heads with the ripened seed over a piece of white paper, according to Fernwood Nursery. Plant them in a sterile seed planting mix and cover with sand. Transplant after a few months.
Hens and chickens are perfect for rock gardens, stone walls, trough gardens and strawberry jars. Europe has a superstitious custom of planting the hens and chickens on tile roofs to prevent lightning strikes.
Hens and chicks will suffer from rot if winters are too wet. The plants may also contract rust. Dispose of any affected leaves in the trash.