One of the factors that makes a great house plant is the foliage. The leaves come in different forms and shapes and it seems that many growers today are drawn to plants with heart-shaped leaves.
The big-leafed alocassias and creeping pothos from the same family are popular but one dainty plant, the string of hearts, is making a name in the house plant scene. Read on to learn more about this delightful entanglement of a plant.
What is the String of Hearts?
Ceropegia linearis subsp. woodii is the formal name given to this plant by Carolus Linnaeus, describing the “fountain of wax” appearance of the flowers. More commonly known as string of hearts, other names include rosary vine, hearts entangled, sweetheart vine, and chain of hearts.
This evergreen plant is native to South Africa, Mozambique, Zimbabwe, and Eswantini, growing naturally on cliff edges and embedded in rock crevices (1).
A member of the dogbane family, the string of hearts plant has characteristically small heart-shaped dark green leaves with heavy white veins and purple-tinged margins. The Variegated String of Hearts have more pronounced markings on the leaves and brighter tinge.
These leaves initially grow close together but as the slender stems elongate, the leaves move further apart, enhancing the stringy appearance of the plant. This cascading growth is best appreciated when planted in a hanging pot.
Along the stems are nodes where small potato-like tubers may grow. They are a way for the plant to store food for regrowth as well as for reproduction. The tuber can produce new stems and roots and is one of the successful ways to propagate a string of hearts (1).
Does Ceropegia Have Flowers?
Throughout the year but mainly in summer and fall, the string of hearts produce odd but attractive flowers. They look like tiny purplish-white vases with long necks and sitting atop are downward-facing hair that traps insects helping the plant pollinate (2).
What is the Lifespan of String of Hearts?
Given the right growing condition, a single plant of string of pearls can grow and live up to 25 years. During its latter years, the plant will decrease in vigor but throughout its lifetime, it can produce over a thousand plants from cuttings, seeds, and tubers (3).
What are the Uses of String of Hearts and is it Toxic?
String of hearts is an effective trailing house plant. It is aesthetically appealing, grows well indoors, and easy to maintain but the leaves and stems are also traditionally used to induce vomiting and treat poisoning.
The plant is safe to grow indoors. In the wild, the tubers from many Ceropegia plants are actually used as survival food and source of water (1).
How to Grow and Care for String of Hearts
Common in many types of house plants is their preference for bright, indirect sunlight and string of hearts is no different. Sudden exposure to strong light may cause sunburn so it is advisable to introduce brighter light gradually to avoid this.
The colors and markings on the leaves are darker and prominent with strong light and tend to lighten under shade. It is also important to note that while the string of hearts grow well in a semi-shaded condition, other growth factors such as watering should be modified to prevent problems.
Ceropegia only requires average watering. The leaves are considered succulent, able to store enough moisture to keep the plant going so this plant can tolerate drought more than wet. Allowing the soil to dry in-between waterings is best for the string of hearts (3).
A well-draining soil is key to prevent its roots from standing water which does not only cause root rot but the infestation of woolly aphids as well (1).
Temperature and Humidity
String of hearts naturally grows in rocky areas of forests so they prefer warm temperature and humid conditions. Grow them indoors where temperature ranges between 25-30ºC. The plant is not heat or frost tolerant so keep them from extreme temperatures. Mist it during hot summer days and when it goes dormant in winter, water the plant sparingly (3).
Pests and Diseases
Aside from the occasional aphids, scale insect, and mealy bug attacks and the root rot disease, the string of hearts does not have a lot of pests and diseases. If there is a mild infestation, manual removal is enough or application of household grade insecticide.
Most of the time, these problems arise because of an improper watering practice so as much as possible, provide only the water required by the plant (2).
Propagation and Maintenance
Propagating Ceropegias is best done during summer, when the plant is in active growth stage. Aside from the underground tubers that can be divided, aerial tubers grow along the stem and if propagating using this method, it is recommended to allow the tuber to root first.
A tuber of about 2cm diameter is required. If the stem is long enough, there is no need to cut it right away. Just place the tuber on top of a sand-perlite mixture in a separate pot and cover with a thin layer of fine sand (1).
With semi-shade and regular misting, feeder roots will develop within 8 weeks. Once the roots have established, the stem can be cut and the new plant will eventually grow new stems and leaves.
String of hearts grow 10cm high and up to 2m in spread. Propagation by stem cutting can be done in time with pruning to make use of the pruned stems instead of discarding them.
Make sure that each cutting has several internodes and leave it submerged in water in a position where there’s good light and temperature. After 2-4 weeks, roots should appear and wait for the cuttings to have established roots before potting (2).
Matured string of hearts will benefit from fertilizer application once a month. They do not require much so feeding at half the recommended rate should be enough in order to avoid fertilizer burn.
Aside from hanging the plant, a potted string of hearts can be placed on top of desks and cabinets where the stems can be allowed to drape from a height. The stems can also be wrapped on a sturdy structure and trained to climb. For full effect and since the plant likes it, let the string of hearts crowd in a pot.
(1) South Africa National Biodiversity Institute. Ceropegia linearis subsp, woodii. http://pza.sanbi.org/ceropegia-linearis-subsp-woodii. Accessed on 22 August 2020.
(2) Mahr, S. “String of Hearts, Ceropegia woodii”. University of Wisconsin. 2010. https://wimastergardener.org/article/string-of-hearts-ceropegia-woodii/. Accessed on 22 August 2020.
(3) Landscape Design & Ecosystem Management. Ceropegia woodii. American University of Beirut Landscape Plant Database. https://landscapeplants.aub.edu.lb/Plants/GetPDF/f37af3cb-6c77-4764-967b-35c1d7989af0. Accessed on 22 August 2020.
*Photo by HanjoHellmann/depositphotos