Sinocrassula
Sinocrassula is a small genus of compact rosette-forming succulents in the stonecrop family Crassulaceae, native to the mountains of Asia. It is best loved among growers for its tight clusters of small, tapering-leaved rosettes — especially the near-black forms of Sinocrassula yunnanensis from Yunnan, China, which have become a quiet favourite on the collector shelf.
Description
Sinocrassula species are low, clumping succulents that form dense clumps or cushions of small rosettes, typically only a few centimetres across. The leaves are narrow, thick and often somewhat pointed or club-shaped, arranged in tight spirals; their colour ranges from grey-green and reddish to the sought-after deep chocolate-to-black tones that appear when plants are grown hard in strong light. Many are short-lived perennials or monocarpic — an individual rosette may flower once and then die — but healthy clumps replace themselves freely from surrounding offsets.
The flowers are small and urn-shaped, borne in clusters on upright stalks and usually cream, pink or reddish. As in much of the family, the bloom is modest compared with the neat, sculptural foliage that makes these plants collectable.
Distribution
The genus is centred on the Himalayan region and southwestern China, with species growing across northern India, Nepal, Bhutan and the Chinese province of Yunnan and neighbouring areas. Plants typically occur on rocky slopes, cliffs and gritty mountain ground, where sharp drainage and seasonal moisture shape their compact, drought-resistant habit.
Notable species
- Sinocrassula yunnanensis — the most widely grown species, forming dense clusters of small rosettes that turn near-black in bright light; the plant most people mean when they say "Sinocrassula".
- Sinocrassula densirosulata — a tightly packed, low-growing species with densely set rosettes.
- Sinocrassula indica — a more variable, wider-ranging species from the Himalayas, often reddish-toned and sometimes behaving as a biennial or short-lived plant.
Cultivation
Sinocrassula are grown much like other small, rosette-forming Crassulaceae. Give them a very free-draining, mostly mineral mix and plenty of light — the darkest colouring in S. yunnanensis only develops with strong, direct sun, while shade turns the plants greener and looser. Water thoroughly once the soil has dried, then allow it to dry again; keep them drier and cooler through winter to avoid rot. See Watering and Repotting for general technique.
They are generally frost-tender and best kept above freezing, though established clumps can tolerate a cool, dry winter rest. Watch for the usual signs of overwatering, as soft, crowded rosettes trap moisture easily.
Propagation
Because rosettes cluster so freely, the simplest method is division — lifting a clump and separating rooted offsets, or removing individual rosettes and rooting them (see Propagation — offsets). Leaf cuttings can also be tried in the manner of other stonecrops, though results are less reliable than with plumper-leaved relatives; see Propagation — cuttings. Species can also be raised from seed, which is useful for the more variable, short-lived kinds where fresh plants are needed to replace those that flower and die.
See also
- Sinocrassula yunnanensis — the signature near-black species
- Crassulaceae — the stonecrop family
- Soil and potting mix · Watering · Propagation — offsets · Propagation — cuttings · Repotting · Pests and diseases