- Name also: Rolling Hen-and-chickens, Hen and Chickens Houseleek
- Latin synonym: Jovibarba sobolifera, Sempervivum soboliferum
- Family: Stonecrop Family – Crassulaceae
- Growing form: Perennial herb. With runners.
- Height: Flower stem 10–20 cm (4–8 in.), leaf rosette 2.5–4 cm (1–1.6 in.) wide.
- Flower: Corolla regular (actinomorphic)–campanulate, pale yellow, approx. 1 cm (0.4 in.) wide; petals 6, with ciliate margins, 15–20 mm (0.6–0.8 in.) long. Calyx 6-lobed, lobes long-ciliate. Stamens 12. Gynoecium with separate leaves, pistils 6. Inflorescence a scorpioid cyme.
- Leaves: In hemispherical rosette and alternate on stem. Rosette leaf blades obovate, curved, short-tapered, glandular-haired, fleshy, with entire margin, often with reddish-brown tips. Stem leaf blades ovate.
- Fruit: Cluster of 6 many-seeded, basally united follicles.
- Habitat: Rocks. Left over from old gardens, sometimes wild.
- Flowering time: June–July.
Rolling hen-and-chicks is a very popular rockery and stone garden plant in Finland. The plant takes a number of years to mature to a size that it is able to flower, after which it dies, so it is only rarely that its exotic inflorescence can be admired. The ornamental species is mainly a fleshy, globose leaf rosette. The rosette breaks off easily from the soil and the plant thus spreads organically from the place it was planted. Rolling hen-and-chicks can be found in Finland as an escape from cultivation in rocky habitats, in the driest and hottest places. Ornamental stands that have gone wild often present the botanist with a problem as the border between a leftover from cultivation, a casual escape and a truly feral plant is often difficult if not impossible to draw. Rolling hen-and-chicks’ natural habitat ends not far from Finland’s south-eastern border, so it is no surprise that the plant thrives here.
Common Houseleek & Cobweb House-leek
Sempervivum tectorum & Sempervivum arachnoideum
Rolling hen-and-chicks’ close relative common houseleek (Sempervivum tectorum) is a similar nectar plant that can often be found growing in old gardens. It used to be planted in Finland on tile and peat-roofed houses to prevent fires. It disappeared almost completely with the modernization of roof structures but it is persistent in the wild, often growing on rocks where the soil is impossibly thin. The plant grows ferally in central and southern Europe and in the mountains of western Asia. The other possible Sempervivum species in Finnish gardens and sometimes outside is cobweb house-leek.
Genus Sempervivum has 42 members, while genus Jovibarba has only 5. The former also cross-breed easily with each other, and breeders have produced hundreds of different varieties. Jovibarba differs from Sempervivum with regards to e.g. the rosettes that are formed at the end of its thin thread-like runners.