Aeonium (tree houseleek) is a genus of about 35 species of succulent, subtropical plants of the family Crassulaceae. The name comes from the ancient Greek “aionos” (ageless). While most of them are native to the Canary Islands, some are found in Madeira, Morocco, and in East Africa (for example in the Semien Mountains of Ethiopia).
The rosette leaves are on a basal stem. Low-growing Aeonium species are A. tabuliforme and A. smithii; large species include A. arboreum, A. valverdense and A. holochrysum.
Aeonium are not frost-resistant. They are related to the genera Sempervivum, Aichryson and Monanthes, which is easy to see from their similar flower and inflorescences. Recently, the genus Greenovia has been placed within Aeonium.