Sempervivum
In German, this genus is part of the Dachwurz or Hauswurz (houseleek). The story goes back in far old days. The ancient Romans named the Dachwurz after Jupiter, the god of thunder, or after his beard (barba jovis - which also refers to the closely related genus Jovibarba). Theophrastus (4th century) also mentions the plant as a roof plant.In large areas of Central Europe, the houseleek was considered a magic plant - planted on the roof, it promised luck to the house and its occupants and protected against lightning. Under Emperor Charlemagne there was an explicit recommendation in the estate ordinance to plant roofing plants such as Sempervivum on the roofs of the estates. In addition to the hoped-for protective effect, witches should be enabled to fly with the help of Dachwurz and show the future. But perhaps a dense growth of roofing plants simply prevents water from flowing straight into the house through a hole in the roof.Simpler and non-magical uses have long been found in the healing arts. Similar to aloe, the thick leaves were placed on the wound for skin irritations, warts or insect bites and also bring relief from toothache. Dachwurz tea is said to help with bronchitis, stomach problems or cramps. So much for the traditions.What we do know: Houseleeks like Sempervivum are tough, nothing can easily faze them - and they can even get along well in barren places. As thick-leaved plants, they store water in their curved leaves and can withstand a long period of time without rain or the watering can. This is easy to care for!