Types of String of Plants: ID & Pet-Safety Guide

Types of String of Plants: ID & Pet-Safety Guide

"String of" plants are a marketing umbrella, not a botanical family. The nickname is pinned to any trailing succulent or semi-succulent whose stems dangle with bead-, heart-, dolphin- or coin-shaped leaves, and the real plants behind those names come from at least four unrelated genera: Curio (formerly Senecio), Ceropegia, Peperomia and Dischidia. That matters for more than trivia, because the genus is what decides whether the plant is safe around a curious cat or dog.

This guide identifies the most popular varieties you will actually find for sale in the US and UK, gives a quick visual tell and a light-plus-water signal for each, and flags every plant's pet-toxicity status individually using ASPCA guidance. The headline you should not skip: the Curio/Senecio strings (Pearls, Dolphins, Bananas, Tears) are toxic, whereas String of Hearts, String of Turtles and String of Nickels are the pet-friendly picks.

Match a string of plants to your space: Snap your room in Growli — we'll measure the light level and tell you which variety will thrive in your conditions.

Related: String of pearls care · string of turtles care · types of succulents

The 9 most common types of string of plants

1. String of Pearls — Curio rowleyanus (syn. Senecio rowleyanus)

Thin, thread-like stems strung with near-perfect spherical, pea-green beads, each with a tiny translucent "window" line down one side. The most recognisable of the group.

Care signal: Bright indirect light, a few hours of gentle direct sun welcome; water only when the beads start to flatten or pucker, then let the gritty mix dry fully. TOXIC to cats and dogs (ASPCA).

2. String of Tears — Curio herreanus (syn. Senecio herreianus)

Looks like a chunkier String of Pearls: leaves are teardrop/lemon-shaped and slightly pointed rather than round, often with darker longitudinal stripes. Larger, more elongated beads than rowleyanus.

Care signal: Same as Pearls: bright indirect light and a deep-but-infrequent soak once the mix is dry. TOXIC to cats and dogs (Senecio/Curio group, ASPCA).

3. String of Bananas — Curio radicans (syn. Senecio radicans)

Glossy, fat, banana- or crescent-shaped leaves that point along fast-growing trailing stems. Faster and more forgiving than Pearls.

Care signal: Bright light including some direct sun; water when the soil is dry and leaves lose firmness. Vigorous trailer. TOXIC to cats and dogs (ASPCA).

4. String of Dolphins — Curio × peregrinus (syn. Senecio peregrinus)

A hybrid of String of Pearls × hot-dog cactus (S. articulatus); leaves curl into little "leaping dolphin" shapes with two side flukes. A true cultivar, sold widely but slower-growing.

Care signal: Bright indirect light, sparse watering once dry. Reverts toward parent leaf shapes if light is low. TOXIC to cats and dogs (ASPCA).

5. String of Hearts — Ceropegia woodii (Rosary Vine / Chain of Hearts)

Wiry purplish stems with widely spaced, marbled silver-and-green heart-shaped leaves; undersides are purple. Often forms little aerial tubers ("beads") along the vine.

Care signal: Bright indirect light keeps the silver marbling crisp; water when the top of the mix dries. PET-SAFE — ASPCA non-toxic to cats and dogs.

6. String of Turtles — Peperomia prostrata

Tiny round-to-oval succulent leaves patterned with pale veining that resembles a turtle's shell; a tight, slow-growing semi-succulent rather than a true desert succulent.

Care signal: Medium-to-bright indirect light, no harsh sun; keep lightly moist and let the top dry between waterings. PET-SAFE — ASPCA lists Trailing Peperomia (Peperomia prostrata) as non-toxic to dogs and cats.

7. String of Nickels — Dischidia nummularia

Trailing epiphyte with flat, round, coin-like ("nickel") leaves spaced along thin stems; a Hoya relative that naturally grows on bark rather than in soil.

Care signal: Bright indirect light and high humidity; water when nearly dry in a chunky/epiphytic mix. Not on the ASPCA database — generally considered non-toxic, but unconfirmed, so verify with your vet and discourage chewing (the latex sap can irritate).

8. String of Buttons — Crassula perforata

Stacked, triangular grey-green leaves that spiral and appear threaded onto the stem, edged in rosy pink in good light. A true stacking Crassula, not a bead-vine.

Care signal: Bright light with some direct sun for the pink edges; water deeply then let dry fully. TOXIC — belongs to Crassula, a genus the ASPCA flags as toxic to cats and dogs (Jade plant, Crassula ovata).

9. String of Frogs — Ficus pumila 'Quercifolia'

A dwarf creeping-fig mutation with tiny lobed, oak-leaf/"frog"-shaped leaves on fine vines — a Ficus, not a succulent.

Care signal: Bright indirect light and steady moisture/humidity (it is not drought-tolerant like the Curio strings). TOXIC — Ficus contains an irritant sap (proteolytic enzyme/ficin) and is considered toxic to cats and dogs.

Are string of plants toxic to cats and dogs?

Toxicity is genuinely mixed across "string of" plants, so always go by the botanical genus, not the nickname. Per ASPCA guidance:

Toxic to cats and dogs (keep out of reach):

• String of Pearls (Curio/Senecio rowleyanus) — the ASPCA's succulent guidance states it "can cause stomach upset — predominately vomiting — and lethargy."
• String of Tears (Curio/Senecio herreanus), String of Bananas (Curio/Senecio radicans) and String of Dolphins (Curio × peregrinus) — same Curio/Senecio genus, containing pyrrolizidine alkaloids and an irritant sap; treat as toxic.
• String of Buttons (Crassula perforata) — a Crassula; the ASPCA lists Jade plant (Crassula ovata) as toxic to dogs and cats, so treat the genus as toxic.
• String of Frogs (Ficus pumila 'Quercifolia') — a Ficus; the irritant sap makes it toxic to cats and dogs.

Pet-safe (ASPCA non-toxic):

• String of Hearts (Ceropegia woodii) — widely reported as ASPCA non-toxic to cats and dogs.
• String of Turtles (Peperomia prostrata) — the ASPCA lists "Trailing Peperomia (Peperomia prostrata)" as Non-Toxic to Dogs, Non-Toxic to Cats.
• String of Nickels (Dischidia nummularia) — not on the ASPCA toxic-plant database; widely considered non-toxic but unconfirmed, so treat with caution and discourage chewing (the latex sap can mildly irritate).

Note: even "non-toxic" plants can cause mild, self-limiting GI upset if a pet eats a lot of foliage, and the Curio/Senecio strings look almost identical to each other — if you cannot confirm the species and a pet has chewed it, contact your vet or the ASPCA Animal Poison Control Center.