Sempervivum 'Black Top'

Sempervivum 'Black Top' in bloom in a sunny garden
Sempervivum 'Black Top'

Cultivar of houseleek, a perennial succulent from the Crassulaceae family. Its hybrid origin is not precisely documented in the reference sources consulted.

It forms dense, low clumps of small, compact, globular rosettes with narrow, upright leaves in bright green to bright yellow-green. The most immediately striking feature is the brown-purple to almost black coloration that covers the leaf tips, contrasting with the vivid green of their base. This sharp, clear bicolor repeated on each leaf of each rosette gives the whole a very distinctive dotted appearance, enhanced by a fine marginal ciliation visible in grazing light.

Stolonization is active; the clumps gradually expand into tight cushions. The rosettes remain small, rarely beyond 3 to 4 cm in diameter, which is perfectly suited for cultivation in pots, troughs, or between the stones of a rock garden.

Culture in full sun is essential to maintain the intensity of the dark tip coloration. Very well-drained, poor to moderate substrate. Perfectly hardy.