String of pearls — Senecio rowleyanus — is one of the most visually distinctive succulents available, and one of the most frequently killed. The trailing stems of spherical, pea-shaped leaves look extraordinary cascading from a shelf or hanging planter, but the plant is less forgiving than its succulent reputation suggests. In UK homes, where light levels are lower than its native South African habitat and where the instinct to water frequently is strong, it fails more often than it thrives.
This guide covers exactly what it needs and where UK conditions specifically create problems.
Light: The Non-Negotiable
String of pearls needs more light than most UK homes naturally provide for much of the year. A south-facing windowsill — directly on the glass, not pulled back into the room — is the correct position. If you have a sunny conservatory, that is better still.
In good bright light, string of pearls grows vigorously, produces long trailing stems, and the pearls remain plump and tightly spaced. In lower light: growth slows or stops, the pearls become smaller and more widely spaced (the stems etiolate, stretching toward the light), and the plant becomes progressively weaker.
A north, east, or west-facing room without a conservatory is genuinely problematic for string of pearls in the UK. The plant will survive but will not thrive, and will be more susceptible to the overwatering that insufficient light invites when owners interpret slow growth as a care problem.
UK winter: Even a south-facing windowsill in UK winter delivers substantially less light than this plant prefers. Between November and February, growth typically stops entirely. This is normal — the plant is resting. Reduce watering to near-nothing during this period. A grow light is the practical solution if you want to maintain active growth year-round or if your position is not south-facing.
Outdoors in summer: Like jade plants, string of pearls benefits enormously from a sheltered, sunny outdoor position from June through August. The higher light levels promote compact, healthy growth. Bring in before nights drop below 10°C.
Watering: Less Than You Think
This is where most string of pearls failures occur. The plant stores water in its spherical leaves — each pearl is a modified, water-storing leaf — and its water requirements are very low compared to non-succulent houseplants.
The rule is: water only when the pearls begin to slightly shrivel or wrinkle. This is the plant’s clear signal that its internal water reserves are depleting. At this point, water thoroughly — until water flows from the drainage holes — then leave it completely alone until the pearls signal again.
The pearl test: Press a pearl gently between your fingers. A well-hydrated pearl is firm and plump. A pearl that needs water is slightly soft and yields under gentle pressure, with a very faint wrinkling of the surface. This is the most reliable watering indicator available.
Never keep the soil moist: String of pearls roots rot extremely rapidly in persistently damp soil. The root system is fine and fibrous, adapted to brief saturation followed by extended dryness. In UK conditions — where cool temperatures and lower light levels slow evaporation — the soil can stay damp for weeks if you water too frequently. At room temperature in a UK winter, a pot can take a month or more to dry adequately.
UK seasonal watering guide:
- Spring (March–May): Water every two to three weeks as growth resumes
- Summer (June–August): Water every ten to fourteen days or when pearls signal
- Autumn (September–October): Reduce to every three to four weeks
- Winter (November–February): Water once a month at most — many UK growers water only once or twice the entire winter
Signs of overwatering: Soft, translucent, or mushy pearls — they collapse when pressed. Blackened or slimy stems. A sour smell from the pot. Unfortunately, by the time these signs are visible, significant root rot has usually already occurred. Act immediately: unpot the plant, trim all rotten roots and stems back to healthy tissue, dust cuts with cinnamon, and repot into completely dry compost. Do not water for two weeks.
Soil and Pot
String of pearls requires extremely well-draining compost. A purpose-made cactus and succulent mix, or standard peat-free compost mixed with at least 50% perlite and coarse grit, is appropriate. The compost should drain in seconds — it should not hold moisture.
Use a small pot, proportionate to the root system. Excess soil volume holds moisture that the roots can’t access, prolonging dampness. Terracotta pots are ideal for the same reason as all succulents: moisture evaporates from the porous walls, helping the root zone dry between waterings.
The plant grows trailing stems that can reach one metre or more — a hanging planter or a pot on a high shelf allows the stems to cascade freely, which is the display form that shows the plant at its best.
Propagation
String of pearls propagates very easily from stem cuttings, and this is the recommended approach if part of the plant is healthy but other sections are struggling.
Take a cutting of ten to fifteen centimetres, remove the pearls from the bottom three to four centimetres of stem to expose bare stem, and allow to callous for a day. Lay the bare stem section on the surface of dry succulent compost and pin it lightly in place, or insert it shallowly into the compost. Do not water for a week. Roots develop in two to four weeks in a warm, bright position.
Spring is the best time to propagate in the UK. Winter cuttings root very slowly in British temperatures and low light.
Common Problems
Mushy, collapsing pearls: Overwatering — the most common cause of death. See watering section above.
Small, widely-spaced pearls with stretched stems: Insufficient light. Move to the brightest available position, ideally a south-facing windowsill.
Shrivelled, dry pearls with no recent watering: Underwatering — water thoroughly and pearls should plump up within twenty-four hours.
Shrivelled pearls despite recent watering: Root rot — the roots are no longer functional and cannot take up water. Unpot and inspect the root system. If roots are brown and mushy, this is a severe overwatering problem despite recent dryness at the surface.
Brown, dry sections at the stem tips: Normal dieback if the stem has reached the floor or a hard surface. Trim back to healthy stem and the plant will branch from the cut.
Also in Mist
Explore Mist rituals & spiritual guides →