String of hearts

String of hearts: how do you recognise it?

Habit

Trailing succulent with thread-thin stems of 1 m or more; the plant itself is about 30 cm wide.

Leaves

Small, fleshy hearts of 1–2 cm in pairs along the stem; dark blue-green with silver marbling, the underside purple.

Tubers

Small aerial tubers form along the stems, and there is a larger tuber in the pot; they store water.

Flower

Sometimes small, tubular flowers of 2–3 cm, pinkish purple with a dark tip, resembling little lanterns.

Roots

Fine and shallow, attached to the tuber: they rot quickly in wet compost.

Plants: March–April · Pruning: March–April

Why grow it?

• A graceful trailing plant: the stems of hearts fall like a curtain over the pot.
• Needs little water: it copes well if you forget to water now and then.
• Tolerates some sun, so it suits a bright windowsill.
• Very easy to propagate from the tubers or by laying a stem on a small pot of compost.
• Small and light: fits in a hanging pot, on a bookcase or on a shelf.

String of hearts: where does it grow best?

• Plenty of light, happily with some sun: an east- or west-facing window is ideal. In strong summer midday sun right behind a south-facing window the leaves can scorch.
• With more light the leaves colour better and stay close together; too dark a spot gives long, bare stems with widely spaced leaves.
• A sandy, fast-draining mix: cactus or succulent compost, possibly with extra coarse sand or perlite.
• Room temperature is fine; in winter it can stand cooler, but not below 10 °C.
• A hanging pot or high shelf, where the stems can trail down freely.

Light

Sunny or bright, out of direct sun

Potting soil

Cactus compost

Acidity

Neutral

Watering

Sparingly

Size

1 m tall, 0.3 m wide

Temperature

Minimum 10 °C

Goes well with

• String of pearls: Another trailing succulent with round ‘pearls’, for the same bright spot and sparing watering.
• Wax plant: From the same family, it also likes plenty of light and little water.
• Echeveria: A compact rosette for a succulent bowl on the windowsill, with the stems trailing over it.
• Haworthia: A small succulent that is happy with the same sandy compost and little water.

String of hearts: when and how to plant it?

Plant in March–April.

1. Repot in March–April, and only when the pot is full of roots, roughly every 2–3 years.
2. Choose a small, shallow pot with a drainage hole; terracotta dries out faster, which is a good thing.
3. Use cactus compost or mix potting compost with a third of coarse sand or perlite.
4. Set the tuber at the same depth as before, just below the surface.
5. Gently untangle the stems and lay them over the rim of the pot.
6. Only water lightly after a few days, so that damaged roots can dry off first.

Care

Watering

Let the compost dry out completely between waterings, then water thoroughly. In summer that is roughly every 1–2 weeks, in winter much less.

Thirst

Soft, limp or wrinkled leaves mean it needs water.

Feeding

From April to September, once a month, a cactus feed at half strength. Not in winter.

Humidity

Dry indoor air is no problem; misting is not needed.

Stems

Untangle the stems now and then and turn the pot so that the plant grows evenly.

Tip: Watch the leaves: plump, firm hearts mean all is well, limp and wrinkled ones ask for water, and yellow, glassy ones tell you that you are giving too much.

String of hearts: when to prune it?

Pruning months: March–April.

When: It does not need pruning. In March–April, trim stems that are too long or bare for a fuller plant.

How:

• Shorten stems that are too long to the length you want, just after a pair of leaves.
• Remove bare, dried-up stems completely.
• Lay the trimmed pieces with tubers back on the pot: they root there and the plant becomes fuller.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Layering

From April to August, lay a stem with a few tubers or nodes on a small pot of lightly moist cactus compost next to the mother plant and pin it down. It roots within a few weeks; then cut it free.

Tubers

Detach the tubers along the stems, ideally with a piece of stem, and press them halfway into lightly moist, sandy compost. Keep them bright and warm; they sprout after a few weeks.

Cuttings

Cut 5–10 cm lengths of stem with a few pairs of leaves and lay them on moist compost, or stand them in a glass of water until roots appear.

String of hearts: how does it get through the winter?

• Not hardy: it stays indoors all year and should not drop below 10 °C.
• In winter it hardly grows: water very sparingly, about every 3–4 weeks, and do not feed.
• A cool, bright spot at 12–15 °C is good, but an ordinary living room also works; then give it as much light as possible.
• In summer it can go outside in a sheltered spot without harsh midday sun, as long as nights stay above 10 °C.

Diseases and pests

• Rot: Yellow, glassy leaves and soft, brown tubers or stems at the base caused by too much water. Let the compost dry out completely, remove rotten parts and take cuttings of healthy stems as a back-up.
• Long, bare stems: Widely spaced leaves and a thin plant caused by too little light. Move it somewhere brighter and lay trimmed stems back on the pot.
• Wrinkled leaves: Too dry: give it a thorough watering. They firm up again within a few days.
• Mealybug: White fluffy tufts along the stems and in the leaf axils. Wipe them off with a cotton bud and cut away badly affected stems.

Through the year

• January: Rest. Very little water, no feeding. Brightest spot.
• March: Repot if the pot is full. Trim stems that are too long.
• April: Trim and lay the pieces back on the pot. Start monthly feeding again.
• May: More water, but let the compost dry out between waterings. Layer or take cuttings.
• June: Growth. Possibly outside in a sheltered, bright spot.
• July: Water every 1–2 weeks, when the compost is dry. Pot up tubers.
• August: Last cuttings. Watch for mealybug.
• September: Last feed. Bring it in before nights drop below 10 °C.
• October: Water less.
• November: Rest. Cool, bright spot.
• December: Rest. A little water every 3–4 weeks.

Did you know?

• The little flowers are traps: small flies crawl in and are briefly held by inward-pointing hairs until these wither. In this way they carry pollen to the next flower.
• It belongs to the dogbane family, like the wax plant and the oleander.
• The tubers along the stems act as a water store: in the wild they help it survive dry periods.