Is Zulu Potato Poisonous? – Toxicity to Humans, Dogs, and Cats

Yes, Zulu potato is poisonous. All parts of the plant contain toxic compounds that can affect humans, dogs, and cats. The bulb holds the highest concentration, but stems, flowers, and roots are also toxic. If a human or an animal chews or swallows any part of this plant, call poison control or your vet immediately.

What Is Zulu Potato?

Zulu potato (Bowiea volubilis) is a succulent plant native to eastern and southern Africa, ranging from Uganda to South Africa. Despite the name, it is not related to the potato you find in grocery stores. It is also not an edible onion, despite its common name “climbing onion.”

The plant grows from a large pale-green bulb (up to 20 cm across) that sits mostly above the soil. From it, twining stems reach up to 4.5 metres, bearing small greenish-white flowers in spring that have an unpleasant odour. The stems themselves look like pale green spaghetti curling upward from the bulb.

Zulu potato belongs to the asparagus family (Asparagaceae). It is widely sold as a houseplant and ornamental, which puts it in homes and gardens where pets and children can reach it.

A note on naming: African potato (Hypoxis hemerocallidea) is a completely different plant. Regular potatoes (Solanum tuberosum) are also unrelated. Do not eat any part of Bowiea volubilis based on its name.

What Makes Zulu Potato Toxic

Two types of toxins are present in Zulu potato.

Cardiac glycosides are the primary threat. These compounds, including bufadienolides such as bovogenin A, disrupt the sodium-potassium pump in heart muscle cells. The result is a buildup of calcium inside cardiac cells, which interferes with the heart’s electrical signals. In plain terms: the plant can cause your heart to beat irregularly or too slowly.

The potency here is not trivial. The cardiac glycosides in the bulb are roughly 30 times stronger than those in foxglove. Those in the flowers are around 60 times stronger. This is not a plant to take lightly.

Calcium oxalate raphides are needle-shaped crystals present in the bulb. On contact with mouth, tongue, or lips, they cause immediate irritation, burning, and heavy drooling. The discomfort comes on fast but usually resolves within minutes.

Which Parts Are Toxic

All parts of Bowiea volubilis are toxic. The bulb is the most concentrated source. Stems, leaves, flowers, fruits, seeds, and roots all contain cardiac glycosides.

In practice, the parts most accessible to pets are the stems, which dogs and cats can reach when the plant sits on a windowsill or shelf. The bulb is the primary risk for children who might handle it during gardening or out of curiosity.

Symptoms of Zulu Potato Poisoning

Symptoms fall into three categories.

Gastrointestinal symptoms are the most common and usually appear within a few hours:

• Nausea
• Vomiting
• Diarrhea
• Abdominal cramping
• Excessive drooling (from calcium oxalate irritation)

Cardiac symptoms occur with larger ingestions and are the serious concern:

• Slow heart rate (bradycardia)
• Heart rhythm irregularities
• Heart block, including complete atrioventricular block
• In severe cases, ventricular fibrillation and death

Skin irritation can occur from contact with bulb sap, especially on moist skin. It is minor and short-lived.

The NC State Extension describes the plant’s poison severity as “low,” which means most exposures cause mild gastrointestinal upset. But “low severity” describes a typical exposure to a stem or leaf. A child or pet that chews into the bulb, or an adult who uses the plant in a herbal remedy, faces a meaningfully higher dose of cardiac glycosides. Livestock deaths and human poisonings from Zulu potato are documented.

Is Zulu Potato Toxic to Dogs?

Yes. Dogs are susceptible to the cardiac glycosides in Zulu potato. If your dog chews or swallows any part of the plant, it can experience vomiting, diarrhoea, and slow heart rate.

Call the ASPCA Animal Poison Control Center at (888) 426-4435 or the Pet Poison Helpline at 1-800-213-6680 (both charge a consultation fee). Bring the plant or a photo of it to your vet for identification.

Seek emergency veterinary care immediately if your dog shows weakness, collapse, or signs of an abnormal heart rhythm.

Is Zulu Potato Toxic to Cats?

Yes. Cats face the same cardiac glycoside toxicity as dogs. They may be attracted to the trailing stems, which can dangle within easy reach on a shelf or hanging planter.

Symptoms in cats mirror those in dogs: vomiting, diarrhoea, excessive salivation, lethargy, and slow heart rate.

Contact the same numbers: ASPCA Animal Poison Control at (888) 426-4435 or Pet Poison Helpline at 1-800-213-6680. Take the plant to the vet.

What to Do If Someone Ingests Zulu Potato

For humans: Call Poison Control immediately at 1-800-222-1222 (US). Do not induce vomiting unless a poison control specialist or medical professional instructs you to do so. Have the plant or a photo ready to describe what was eaten and how much.

For dogs and cats: Call ASPCA Animal Poison Control at (888) 426-4435 or Pet Poison Helpline at 1-800-213-6680. Take the plant to the emergency vet. If possible, note approximately how much was ingested and when.

Seek emergency care immediately if a human or animal shows cardiac symptoms: slow pulse, fainting, collapse, weakness, or difficulty breathing.

Is Zulu Potato Safe to Grow at Home?

Zulu potato is a popular houseplant and, with care, it can be grown safely. Keep it out of reach of pets and children. Place it on a high shelf or in a room with a closed door. Wear gloves when handling the bulb, especially when repotting.

The plant is also collected from the wild in parts of its native range, and its conservation status is listed as vulnerable due to overharvesting. If you are growing it, you are participating in a tradition of cultivation that helps reduce pressure on wild populations.

FAQ

Is Zulu potato the same as African potato? No. African potato refers to Hypoxis hemerocallidea, a different plant entirely. Do not confuse the two.

What happens if my dog eats climbing onion? Expect vomiting, diarrhoea, and possibly slow heart rate. Call your vet or ASPCA Animal Poison Control right away. Do not wait for symptoms to worsen.

Is the Zulu potato bulb edible? No. The bulb contains the highest concentration of cardiac glycosides and calcium oxalate crystals. Eating it can cause serious cardiac effects. It is not food.

Are there safe alternatives to Zulu potato? If you want a non-toxic houseplant with a similar look, consider spider plant (Chlorophytum comosum) or Boston fern (Nephrolepis exaltata). Both are safe for cats and dogs.