Sempervivum — 20 species

Sempervivum, known as hens and chicks or houseleeks, are compact rosette-forming succulents that spread readily by producing offsets around a central "hen" plant. Species such as Hairy Houseleek and Pitton's Houseleek are exceptionally tough, thriving in full sun with very well-drained or rocky soil and needing only infrequent watering — they are among the most drought-tolerant plants available. All Sempervivum species are non-toxic to cats and dogs according to the ASPCA, making them an excellent choice for pet-safe rock gardens, containers, and green roofs.