String of hearts care: light, water and the pink varieties

String of hearts (Ceropegia woodii) is a trailing succulent vine that does best in bright light, a gritty fast-draining mix, and watering only once the soil is dry all the way through. Its thin purple vines carry small heart-shaped leaves marbled with silver, and in good light they hang 3 feet or more from a pot.

Almost all failures come from two things: soil that stays wet, which rots the roots and tubers, and low light, which turns a full plant into a few bare strings. Get those right and it is one of the easiest trailing plants you can grow.

What string of hearts is

String of hearts is a semi-succulent from southern Africa in the milkweed group. The RHS, which lists it as Ceropegia linearis subsp. woodii and gives it its Award of Garden Merit, describes an evergreen tuberous perennial with trailing stems of 3 feet (1 m) or more, heart-shaped gray-patterned leaves purple underneath, and lantern-shaped pink-purple flowers about 3/4 inch long.

The "tuberous" part matters. At the base it forms a potato-like tuber, and along the vines it makes small round aerial tubers at the leaf joints. They store water, which is why the plant handles drought well and rots easily when kept wet.

Light

University of Wisconsin Extension recommends a west or south window, and notes that strong light gives darker leaves with clear silver marbling, while low light gives pale green leaves.

Hang it at or just above window height, not up near the ceiling where light falls off. Under a grow light it does well 6–12 inches below an LED panel for 12–14 hours. Leaves that turn reddish-purple in strong sun are stressed but fine; crisped, bleached leaves mean it is too close to hot glass.

Watering

Water only when the soil is dry all the way through, then soak until water drains from the bottom. Wisconsin Extension stresses that it is easily killed by overwatering and tolerates drought far better than excess moisture.

Check with a wooden skewer pushed to the bottom of the pot, or lift it: a dry pot is noticeably light. Slightly soft, thin-feeling leaves are a safe signal to water. Wrinkled leaves in wet soil mean the opposite: the roots have rotted and cannot take up water. Read more in overwatering and our watering guide.

Soil and pot

Use a cactus and succulent mix with 30–50% extra perlite or pumice. A small, shallow terracotta pot with a drainage hole is ideal: it dries fast and the plant has a shallow root system. The RHS recommends cactus compost. Repot only when the tubers crowd the surface, every 2–3 years in spring, into a pot just an inch wider. See soil and pots.

Temperature and humidity

Ordinary room temperatures of 65–85°F suit it. Wisconsin Extension recommends keeping it above 60°F in winter; the RHS rates it as needing frost-free protection. Normal home humidity is fine; it does not need a humidifier. Keep it away from cold windows in January and from heat registers, which dry the thin stems.

It can summer outdoors in bright shade once nights stay above 55–60°F, and in USDA zones 10–12 (NC State Extension) it can be grown outside in hanging baskets year-round.

Fertilizer

Feed lightly: a balanced or cactus fertilizer at quarter to half strength once a month from April to September, nothing in winter. Too much fertilizer gives long, weak vines with widely spaced leaves. See our fertilizer guide.

Variegated, pink and Silver Glory

Wisconsin Extension describes the variegated form, C. woodii f. variegata, as having cream and pink variegated leaves. "Pink string of hearts" in listings is almost always this form grown in strong light; the color fades to cream and green in a dimmer spot. If a variegated vine produces stretches of pure green, cut them off at the base or they will outgrow the rest.

Propagation

Wisconsin Extension notes it roots from vine cuttings, best with bottom heat, and from the aerial tubers, which can be pressed into soil while still attached to the vine.

1. Tuber pinning. Lay a vine across a small pot of moist gritty mix so the round tubers touch the soil; hold it with a bent paper clip. Roots and new shoots form in 2–4 weeks; then cut the vine from the mother plant.
2. Cuttings in water. Cut 4–6 inch pieces with at least 2 nodes, strip the lowest leaves, and set them in a small jar of water at 70–80°F in bright light. Roots in 2–3 weeks; pot up when they are an inch long.
3. Cuttings on soil. Coil cuttings on top of barely moist succulent mix and mist the surface every few days until they root.

Pinning vines back into the mother pot is also how you fix a bare top. More in our propagation guide.

Flowers

String of hearts flowers mostly in summer and fall in good light. Wisconsin Extension describes inch-long flowers with a bulbous base and a tubular corolla in white to pale magenta, with petals fused at the tips into a cage that briefly traps small pollinating flies. They have no noticeable scent and need no special care. Occasionally pollinated flowers produce thin paired seed pods.

Pests

Wisconsin Extension reports few pests, with mealybugs the main problem: look for white fluff in leaf joints and on the tubers. Spider mites appear in hot, dry spots. Fungus gnats only show up when the soil stays wet; let it dry and see pestfact.com's fungus gnat guide.

Is string of hearts toxic to cats?

The ASPCA plant list for cats does not include Ceropegia woodii in either its toxic or non-toxic section, so there is no official ASPCA classification. It is widely regarded as non-toxic and has no known toxic principle, but any plant material can upset a cat's stomach, and dangling vines invite chewing. Hang it out of reach. If your cat eats a lot of it or seems unwell, call your vet or the ASPCA Animal Poison Control Center at (888) 426-4435. For proven options, see pet-safe plants.

Where to use it

It is at its best in a hanging pot or on a high shelf by a bright window, where the vines can fall freely. Long strands can be trimmed at any length; cut pieces root. For more cascading plants see trailing plants, and if you like the succulent side of its care, see succulents.

Buying and repotting a new plant

Look for a pot with many vines and leaves close together along the stems; long gaps between leaves mean the plant grew in low light. Avoid pots with yellow, translucent leaves near the soil, which point to rot. Many store plants are sold in a peat-heavy mix that holds too much water. If yours stays wet for more than a week after watering, repot it in spring into a gritty cactus mix in a small terracotta pot, keeping the main tuber at the soil surface rather than buried.

When handling the plant, gather the vines over your arm first; they tangle and snap easily. Untangle long strands by laying the pot on its side on a table and teasing them apart from the ends.

Seasonal care calendar

Pruning and keeping it full

You can trim string of hearts at any time of year with clean scissors. Cutting a vine does not make it branch the way a pothos does, so trimming alone will not make it bushier, but every piece you cut is a potential new plant. The best routine is to take the longest vines each spring, coil or pin them back onto the soil in the same pot, and let them root. Within a season the top of the pot fills in and the trailing curtain stays dense.