The tight, spreading foliage rosettes of sempervivum plants makes them easily recognisable, and the nearly 40 wild species and countless cultivars found around the world endear themselves to many gardeners for their hardiness and ornamental value. Most sempervivum species bear the common name "hen and chicks" for the many small offshoots that surround the main plant, which give the plants their characteristic appearance and provide a simple means of propagation. Propagating sempervivums from offshoots is very simple, and the process is identical and highly successful regardless of the species.
Lift the edge of a healthy, mature sempervivum plant to expose the stolons, or horizontal runners, attaching the parent plant to the offshoots. Look for offshoots with a withered or dried-out stolon.
Snip the stolon using a pair of floral snips, pruners or scissors. Set the sempervivum pup in a cool, shady spot while preparing a pot for it.
Fill a 6-inch pot with a mixture of 3 parts succulent potting mix, 2 parts medium-grit sand and 1 part perlite. Fill the pot to within 1 inch of the top.
Set the sempervivum pup on the surface of the soil mixture. Backfill around it with small amounts of additional soil until the bottom leaves rest on the surface. Press the soil lightly with your fingertips to anchor the pup.
Pour 5 or 6 tbsp of water into the pot to lightly moisten the soil. Withhold additional watering for seven to 10 days. Water the plant again with 5 or 6 tbsp of water. Allow the soil to dry out completely between waterings to stress the offshoot and prompt it to grow roots.
Keep the sempervivum pup in a spot near a source of diffuse light where temperatures stay above 21.1 degrees C during the day. Avoid direct sunlight exposure while the plant is rooting.
Transplant the rooted sempervivum pup into a permanent pot or garden bed once the leaves plump up and it begins to put on growth. Plant it under the same conditions as the mother sempervivum.