Sempervivum - a low-maintenance and hardy plant
Sempervivum - also called houseleek or rock rose - owes its Latin name to its resilience, because sempe rvivum always means alive. The thick-leafed plants tolerate cold, as well as drought or heat. Most of the more than 50 species of houseleek are rather inconspicuous with their rosettes of leaves. However, due to the diversity of species and the different colours, Sempervivum is very popular with plant collectors.
Appearance and growth of houseleek
The thick-leafed plants come in shades of green, orange and red, depending on the type and intensity of the sunlight. The shape and size of the flowers also varies. The rosette-like shape is due to the shortened shoot axis.
The rock rose can produce flowers between May and August. From the centre of the leaf rosette the flower stalks then grow up to 60cm long. However, as soon as the plant has flowered, the leaf rosette dies. The formation of daughter rosettes, however, ensures the survival of the succulents and they spread to form large mats.
Location and care of houseleeks
Like most succulents, the houseleek is not very fussy about where it is planted and how it is cared for. In nature, houseleeks often grow in mountains or in rock crevices, so they are well suited for planting in rock gardens or flat roofs. The only thing the rockrose cannot tolerate is waterlogging. When watering sporadically, care should also be taken to ensure that no water gets into the rosette of fat leaves, as otherwise weeds can develop. So only water a little during prolonged dry spells and only moisten the soil.
Sempervivum is usually planted with other succulents such as wall pepper or fat leaf Cape Blanco In the garden, thick leaf spices also harmonise with Mediterranean plants, such as thyme, because of their similar requirements. However, planting in a bowl or on the windowsill together with other species of houseleeks is also very popular.
If the succulents are to be planted in a pot, cactus soil is best. Alternatively, a low-nutrient substrate consisting of two-thirds sand and one-third potting soil can be mixed. However, it is important to provide a drainage layer and drainage holes in the planting container to prevent waterlogging.
Use as a medicinal plant in the Middle Ages
Succulents were already very popular in the Middle Ages because they were believed to protect the house from lightning. In addition to its magical effect, the thick-leaved plant was also used as a medicinal plant. As a tea, the leaves helped with nausea and stomach ulcers, and they were also said to have a blood-cleansing effect. Used externally, they had an anti-inflammatory and decongestant effect and could therefore be used for itchy skin or insect bites.