String of Buttons

How to care for String of Buttons

Light

Crassula perforata thrives in bright light and appreciates several hours of direct sun each day, ideally from a south- or east-facing windowsill. Adequate light is essential for maintaining the compact, tightly stacked growth habit and the attractive pinkish leaf margins. In lower light conditions the stems become etiolated and the plant loses its characteristic form.

Watering

Water thoroughly but infrequently, allowing the compost to dry out completely between waterings. During the growing season (spring through early autumn) this typically means watering every 10 to 14 days, depending on pot size and ambient temperature. In winter, reduce watering significantly, perhaps once a month, as the plant is dormant and vulnerable to root rot if kept too moist.

Soil and potting

A very free-draining compost is essential. Use a commercial cactus and succulent compost or mix standard peat-free potting compost with at least 50 per cent coarse horticultural grit or perlite. Good drainage prevents the root rot to which all Crassula species are susceptible. Terracotta pots are particularly suitable as they help wick away excess moisture.

Feeding

Feed once a month during spring and summer with a balanced or low-nitrogen liquid fertiliser diluted to half the recommended strength. A fertiliser formulated for cacti and succulents is ideal, as these typically have a lower nitrogen ratio that discourages soft, lax growth. Do not feed during autumn and winter when the plant is resting.

Humidity and temperature

This species tolerates and prefers low humidity, making it well suited to typical UK indoor environments. Ideal temperatures range from 10 to 27 C. It can tolerate brief dips to around 5 C but should not be exposed to frost. Avoid placing it near cold draughts in winter or directly above radiators that create very dry, hot air currents.

Repotting

Repot every two to three years or when the plant has clearly outgrown its container. Choose a pot only one size larger, as an oversized pot retains excess moisture and increases the risk of root rot. Spring is the best time to repot. Allow the plant to settle without watering for a few days after repotting to let any damaged roots callous over.

Pruning

Pruning is not strictly necessary but can be carried out in spring to maintain a tidy shape and encourage bushier growth. Pinch or cut back any excessively long or leggy stems just above a leaf pair using clean, sharp scissors or a knife. Removed stem sections can be used as cuttings for propagation. Clear away any dead leaves from the base of the plant to improve air circulation.

Is String of Buttons toxic?

Common problems

How to propagate

Stem cuttings

Cut a healthy stem of 5 to 10 cm in length, remove the lower leaves, and allow the cut end to callous for one to two days. Insert into dry, gritty compost and wait one to two weeks before watering lightly. Roots typically develop within three to four weeks.

Leaf cuttings

Gently twist a healthy, plump leaf from the stem to ensure a clean separation at the base. Lay the leaf on the surface of barely moist succulent compost and place in bright, indirect light. Tiny plantlets may emerge at the base over several weeks, though success rates are lower than with stem cuttings.

Where String of Buttons comes from

Native to Eastern Cape, South Africa, Western Cape, South Africa, KwaZulu-Natal, South Africa.

Story and origins

The genus name Crassula derives from the Latin word 'crassus', meaning thick or fat, a reference to the characteristically fleshy, water-storing leaves common to all members of the genus. The species epithet 'perforata' comes from the Latin 'perforatus', meaning pierced through or perforated, describing the apparent visual illusion that the stem passes through the fused or closely pressed leaf pairs, as if the stem has been threaded through holes in the leaves.

Crassula perforata was formally described by the Swedish botanist Carl Peter Thunberg, a student of Carl Linnaeus, during his botanical surveys of the Cape Colony in the late eighteenth century. Thunberg's extensive fieldwork in South Africa between 1772 and 1775 yielded descriptions of a great many new succulent species. The plant gradually entered cultivation in Europe as interest in South African flora grew throughout the nineteenth century, and it became established as an ornamental succulent in glasshouses and later in homes. It has no particular folklore or cultural symbolism attached to it, though in its native South Africa it forms part of the diverse succulent flora of the Karoo and Eastern Cape that has long attracted botanical interest.

Varieties to know

Crassula perforata 'Variegata'

Leaves are marked with creamy-yellow margins alongside the grey-green centre, retaining the typical pink blush on the leaf edges in good light.

Crassula perforata subsp. kougaensis

A naturally occurring subspecies with slightly narrower leaves and a more compact growth habit, found in a restricted area of the Eastern Cape.

Fun facts

• The stems of Crassula perforata appear to thread directly through the centre of the stacked leaf pairs, which is the origin of the common name 'String of Buttons'.
• In the wild, Crassula perforata often grows in rocky quartz patches and among fynbos scrub, where it scrambles through other low shrubs for support.
• The small, star-shaped flowers produced in spring are pale yellow to white and attract small insects, though the plant rarely flowers indoors without a period of cool, bright conditions.
• Like many succulents, Crassula perforata uses Crassulacean Acid Metabolism (CAM) photosynthesis, opening its stomata at night rather than during the day to minimise water loss.
• The genus Crassula contains over 200 species, making it one of the largest genera in the Crassulaceae family, and the majority are native to southern Africa.

String of Buttons FAQ