String of pearls is an unusual succulent with nearly spherical leaves from South Africa. The plant was recently moved from the large genus Senecio (which includes succulents and common weeds like common groundsel) to the new genus Curio. It was named after the British botanist Gordon Rowley. However, it is still likely to be known as Senecio rowleyanus in the gardening world and in books. This soft, evergreen perennial plant is from the daisy family (Asteraceae) and grows naturally in dry parts of the eastern Cape of South Africa. There is also a variegated form with wide white stripes and sections (which might actually be S. hirta, which has round leaves that are a bit bigger, longer, and striped; it is also known as string of pearls or string of beads. The plant has weak surface roots that send out trailing stems that can be up to three feet long. These stems can root where they touch the ground and form dense mats. It often grows under bushes or between rocks which provide some protection from intense sunlight. These are the alternate leaves that store water. They are about the size and shape of small peas, with a pointy end and a thin dark green stripe running along the side. The round shape of the leaves reduces the amount of surface area that is exposed to dry desert air, which lowers the amount of water that evaporates. However, this also means that photosynthesis can’t happen as much as it could on a normal thin, flat leaf. Darker, see-through tissue on the side of the leaf acts as an “epidermal window” that lets light into the leaf, making more space for photosynthesis. Several other succulents from southern Africa, like the related Senicio radicans, and baby toes (Fenestraria spp.) have also adapted to dry places in this way. ) and Haworthia cooperi which grow underground, exposing only the leaf tips. String of Pearls blooms in the summer, with white discoid flowers that look like daisies and have long red stamens and bright yellow anthers on 1½ inch long stems. The small flowers don’t stand out, but they do smell nice. The scent is said to be sweet and spicy, like cinnamon. After the flowers come many seeds, each with a white, cottony covering that helps the wind spread them. String of pearls is commonly grown as a houseplant or an outdoor ornamental in frost-free climates. It is often grown in hanging baskets to allow the trailing stems to spill downward. It could also be grown in a flat dish, which would let it keep growing in a way that looks like it does in the wild. For the growing season, indoor containers can be moved outside, but they need to be brought used to the sun slowly so they don’t get burned. They should also be kept out of the rain, and they need to be brought back inside before frost. Like most succulents, this one doesn’t need much care. It just needs bright light, soil that drains well, and only a little watering every so often. Root rot from overwatering is the most common cause of its demise. Grow plants in cactus mix or potting medium that drains well. You can also mix in inorganic materials like pea gravel, sharp sand, poultry grit, or pumice (up to a 1:1 ratio). Utilize a shallow pot since the plants won’t be able to grow deep roots (and if they can’t quickly remove water from a large soil volume, they will be more likely to develop root rot). Clay pots are better than plastic or ceramic ones because they let water evaporate through the sides more quickly, drying the soil out. Let the soil in the pot dry out completely between waterings. When the plant is not actively growing, give it more water in the summer than in the winter. Providing a rest period during the winter with cool (55-60°F). Dry conditions may promote blooming in summer. Plants need to be watered when the leaves start to look a bit shriveled. Repot every year or two or fertilize lightly in spring. Mealybugs or aphids may infest plants but otherwise they have few pest problems. The leaves are slightly poisonous; eating them may make you throw up or have diarrhea. The plant’s sap may irritate or rash sensitive skin. Propagate string of pearls by taking 3-4 inch stem tip cuttings. Take off three to four leaves from the bottom of the cutting and put it in or on wet potting mix, making sure to just cover the last few bottom nodes. Roots should start to grow at each node right away. Mist the soil surface to avoid overwatering until the roots are established. This plant can also be grown from seed but it is not commonly available. – Susan Mahr, University of Wisconsin – Madison.
String of pearls, also known by its scientific name Curio rowleyanus, is a unique and fascinating succulent plant that grows in the wilds of South Africa. In this article, we’ll explore the natural habitat and growth habits of string of pearls, how it has adapted to survive in arid environments, and what we can learn from this resilient plant.
String of pearls is a creeping, perennial succulent vine that forms dense mats along the ground Its stems can reach up to 3 feet long, trailing and rooting where they touch the soil. This allows the plant to spread horizontally across the landscape
The most distinctive feature of string of pearls are its spherical, pea-sized leaves. These unusual round leaves are an adaptation to help the plant retain water in the dry desert climate where it grows Each pearl-shaped leaf has a small point on the end and is about 1/4 inch in diameter An interesting trait is the translucent “window” band along the leaf edge that allows light into the interior to enhance photosynthesis.
The Natural Habitat of String of Pearls
In the wild, string of pearls is native to the arid regions of South Africa. It grows in the eastern Cape Provinces, which have a dry, desert-like environment.
String of pearls often takes advantage of the shade provided by bushes, rock outcroppings and boulders. This allows it to avoid the harsh direct sunlight that would dry it out quickly. It flourishes in areas with fast-draining, sandy soil.
The natural conditions where string of pearls thrives have scant rainfall, intense sun exposure, and extreme temperatures shifts. Days can be blazing hot while nights get quite cold. These harsh environs have shaped the physical adaptations that allow string of pearls to prosper.
Physical Adaptations for Survival
String of pearls has evolved several specialized traits to manage life in a harsh desert landscape. These physical adaptations help it maximize water storage while minimizing evaporation. Understanding these tactics can provide insight for growing string of pearls successfully.
Spherical Leaf Shape – The round shape minimizes surface area exposed to the dry air. This lessens water loss through evaporation.
Tiny Size – The small pea-sized leaves further restrict the surface that can lose moisture.
Succulent Texture – The thick, fleshy interior stores water for long periods.
Window Band – The translucent tissue allows light into the leaf, boosting photosynthesis.
Trailing Growth – Long stems hug the ground, finding pockets of shade and moisture.
Rooting Stems – Wherever the stems touch soil, they root to spread widely and gather water.
Matted Growth – Dense horizontal mats help shade the soil, reducing evaporation.
Growing Conditions in the Wild
To understand string of pearls care, it helps to consider its native landscape and growing requirements:
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Hot, sunny weather with temperatures from 65°F to over 100°F.
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Low annual rainfall, often less than 20 inches per year.
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Fast-draining, sandy soil that avoids standing moisture.
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Very low humidity, with arid desert conditions.
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Shaded microclimates under bushes that offer protection.
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Daily temperature shifts from extremely hot days to cold nights.
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Bright light is essential, but sheltered from direct sun during the hottest hours.
How String of Pearls Adapted to Thrive
Through evolutionary changes over time, string of pearls developed special traits that enable it to prosper in harsh desert environments. These include:
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Round leaves that minimize surface area to retain moisture.
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Tiny succulent leaves that store water.
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Translucent leaf windows to maximize interior photosynthesis.
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Trailing stems that hug the ground, seeking shade.
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Rooting stems to spread widely and gather scarce water.
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Dense mats that protect the soil from drying out.
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Slow growth and low water needs allow survival in droughts.
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Closing leaf pores (stomata) during the day to prevent water loss.
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Opening pores at night to absorb moisture from cooler air.
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Ability to go dormant during temperature extremes to survive.
The Remarkable Resilience of String of Pearls
The adaptations of string of pearls provide insights into how specialized traits allow plants to carve out niches in challenging environments. Understanding the ecology and growth habits of string of pearls can help us be better caregivers by replicating favorable conditions.
In your own garden, string of pearls can add unique beauty and remind you of the wonders of the plant kingdom. By observing and learning from its extraordinary evolutionary adaptations, we can appreciate the amazing resilience of string of pearls in the wild.
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