Sempervivum arachnoideum is the most common “cobweb” species of semps, forming a spiderweb-like pattern of white filament on top of its rosettes. They typically bloom pink. The Forest Frost variety of this species has olive green rosettes with outer leaves ranging from dull red to a deep burgundy, providing a slightly darker color palette than other arachnoideums. This variety is mid-sized for cobweb semps. Mother plants can produce up to nine chicks each per growing season.
A classic hardy succulent, sempervivums, known also as hens and chicks, houseleeks, and, as I call them, “semps”, are tough, easy-to-care-for plants native to the Alps of central Europe. The color of their evergreen foliage will often change throughout the year. In spring, early summer, and sometimes even fall, mature rosettes send out one to dozens (depending on species and variety) of stolons a short distance from the plant, forming a ring of baby semps around the mother plant. This is where their common name comes from. In summer, some of the mother plants will send up show sprays of flowers, lasting for several weeks. After flowering, the rosette will die, but the chicks it previously produced quickly grow in to take its place.
Semps can grow almost anywhere. Traditional succulent locations, such as rock gardens and containers, work great. They will also thrive almost anywhere in the landscape provided they don’t get completely flooded. With a small amount of supplemental soil, they can grow on logs, mailboxes, green roofs, and nearly any other location. They do not perform well indoors, however, as they become leggy and lose color in extreme low light.
- Mini: This plant is sold as a rooted offset and/or plug.
- Max height: 12″
- Max spread: 12″
- Hardiness: USDA Zones 5-10
- Light: Full sun to part shade
- Water: 1x per week during the heat of summer
- Soil: Well-drained
- Wildlife: deer resistant