12 Toxic Houseplants to Keep Away From Pets and Children in the UK

Houseplants have never been more popular in British homes. From the bold monstera leaves draping over Ikea shelving units to the trailing pothos spilling out of macramé hangers, we’ve collectively gone plant mad — and for good reason. They clean the air, lift our moods, and make even the dreariest north-facing flat feel a little more alive.

But here’s the thing that garden centres don’t always shout about loudly enough: a significant number of the UK’s most popular houseplants are genuinely toxic to cats, dogs, and young children. Not just mildly irritating — some can cause serious organ damage or worse if ingested. As a nation of pet lovers (there are an estimated 34 million pets in the UK as of 2024), this is information every plant owner needs.

This guide covers 12 commonly sold houseplants that pose real risks, what those risks actually are, and how to keep everyone in your home safe without giving up your love of indoor greenery entirely.

Why Toxicity in Houseplants Is a Bigger Issue Than You Might Think

The RSPCA and Cats Protection both receive thousands of calls every year related to plant ingestion. The Animal Poison Line, a UK-based service staffed by veterinary toxicologists, reported that plant-related calls are consistently among their most common enquiries. Children under five are also particularly vulnerable, as they’re naturally curious and tend to put things in their mouths without hesitation.

Toxicity doesn’t always mean instant drama. Some plants cause mild gastrointestinal upset — vomiting, drooling, diarrhoea — while others can affect the heart, kidneys, or central nervous system with far more serious consequences. Knowing which is which makes all the difference.

The 12 Houseplants You Need to Know About

1. Peace Lily (Spathiphyllum)

The peace lily is one of the UK’s best-selling houseplants, stocked everywhere from Waitrose to B&Q for around £8–£20. It thrives in low light, rarely complains, and produces elegant white blooms. It’s also genuinely dangerous to cats and dogs.

Peace lilies contain calcium oxalate crystals. When chewed, these microscopic crystals cause an immediate burning sensation in the mouth, excessive drooling, and swallowing difficulties. Cats and dogs that ingest larger amounts may vomit repeatedly and show signs of distress. Importantly, while peace lilies are not true lilies (and so don’t cause the catastrophic kidney failure associated with Lilium species), they’re still best treated with caution. Keep them on high shelves or in rooms your pets don’t access.

2. True Lilies (Lilium and Hemerocallis species)

This one needs to be said clearly and without softening: true lilies are potentially fatal to cats. All parts of the plant — flowers, leaves, stem, pollen, and even the water in the vase — can cause acute kidney failure in cats. There is no safe level of exposure.

Common varieties sold in UK supermarkets and florists include Easter lilies, tiger lilies, and stargazer lilies. They’re often gifted in bouquets without any warning labels. If you have a cat, these plants should not enter your home at all. If your cat has come into contact with lily pollen — even just brushing against a flower — wash them immediately and contact your vet or the Animal Poison Line (0800 213 6680) straight away.

3. Pothos / Devil’s Ivy (Epipremnum aureum)

Pothos is practically inescapable in UK homes and offices right now. It’s forgiving, fast-growing, and looks wonderful trailing from a high shelf. It’s also toxic to cats and dogs due to — once again — calcium oxalate crystals.

Symptoms after ingestion include oral irritation, vomiting, and drooling. It’s rarely life-threatening, but it will cause your pet significant discomfort. Given how much pothos tends to trail and droop within reach of curious animals and toddlers, placement is key. Keep it genuinely out of reach, not just theoretically out of reach.

4. Dieffenbachia (Dumb Cane)

The common name “dumb cane” tells you something important: this plant causes temporary speechlessness. Dieffenbachia contains calcium oxalate crystals so concentrated that chewing a leaf can cause severe swelling of the mouth, tongue, and throat, potentially making it difficult to speak or swallow.

This is a serious risk for young children. In rare cases, swelling can be severe enough to affect breathing. Dieffenbachia is widely sold in UK garden centres and looks deceptively benign with its large, variegated leaves. Wear gloves when handling it yourself — the sap is an irritant — and keep it well away from children and pets.

5. Philodendron

Philodendrons have had a moment in recent years, and varieties like the heartleaf philodendron and the split-leaf philodendron (often confused with monstera) are now found in homes across the country. They’re attractive and easy to grow, but like their relatives in the Araceae family, they contain calcium oxalate crystals.

Both cats and dogs can experience oral irritation, excessive drooling, and vomiting if they chew on the leaves. In more serious cases, there may be difficulty swallowing and lethargy. Place philodendrons where pets cannot reach them — remembering that cats in particular are excellent climbers and jumpers.

6. Monstera deliciosa (Swiss Cheese Plant)

The monstera has become something of a symbol of the modern British home, featuring on everything from cushion covers to wallpaper. The plant itself, however, is also a member of the Araceae family and carries the same calcium oxalate risk as philodendrons and pothos.

Monstera is toxic to cats and dogs. The scale of a mature monstera — some grow to ceiling height — means there’s a lot of plant for a pet to get into. The large leaves are also relatively easy to chew. This doesn’t mean you have to rehome your monstera, but you do need to be thoughtful about where it lives in your home.

7. Aloe Vera

Aloe vera is often held up as a wonder plant — soothing sunburn, allegedly purifying air, looking architectural on a kitchen windowsill. It’s sold in virtually every supermarket in the UK for under £5. And yet it’s toxic to both cats and dogs.

The toxic components are anthraquinone glycosides found in the latex layer of the leaf (the yellowish sap just beneath the green skin, distinct from the clear inner gel). Ingestion can cause vomiting, diarrhoea, lethargy, and in larger amounts, changes in urine colour and tremors. It’s not usually life-threatening, but it can make your pet quite unwell. Place it on a high windowsill or in a room your animals don’t frequent.

8. Sago Palm (Cycas revoluta)

The sago palm looks like a miniature tropical palm tree and has grown in popularity as a statement plant for living rooms and conservatories. It is, without question, one of the most dangerous plants you can have in a home with pets.

Every part of the sago palm is toxic, but the seeds (nuts) contain the highest concentration of cycasin, a toxin that causes severe liver failure in dogs. The mortality rate following ingestion is high even with prompt veterinary treatment. Vomiting typically begins within a few hours; liver failure can follow within days. The sago palm should simply not be in any home with dogs. Full stop.

9. Oleander (Nerium oleander)

Oleander is more commonly found in UK gardens than indoors, but it is occasionally grown as a conservatory or patio plant and sometimes sold at garden centres. Every part of this plant — including the smoke from burning it — is toxic to humans, dogs, cats, and horses.

Oleander contains cardiac glycosides that disrupt the heart’s electrical activity. Symptoms include severe vomiting, drooling, low heart rate, and in serious cases, heart arrhythmias. This is a medical emergency requiring immediate veterinary attention. If you grow oleander outdoors, ensure fallen leaves are cleared regularly, as dried leaves retain their toxicity.

10. Ivy (Hedera helix)

English ivy is so commonplace in the UK — both indoors and climbing every other garden wall — that it’s easy to forget it carries any risk at all. As a houseplant, it’s a popular trailing option for hanging baskets and high shelves.

The leaves and berries contain triterpenoid saponins and polyacetylene compounds that are toxic to dogs, cats, and humans. Skin contact with the sap can cause dermatitis in sensitive individuals, and ingestion leads to vomiting, diarrhoea, excessive drooling, and abdominal pain. It’s rarely life-threatening if only a small amount is eaten, but it will cause notable discomfort. The berries — which appear if the plant is grown outdoors — are more toxic than the leaves.

11. Cyclamen

Cyclamen are everywhere in UK shops from autumn through to early spring, brightening up supermarket checkouts and garden centre displays for as little as £3–£5. They’re cheerful, compact, and bloom reliably. They’re also toxic to cats and dogs, particularly at the root level.

The highest concentration of toxic saponins is found in the tubers (the bulb-like roots), though the leaves and flowers also contain them. Eating the leaves typically causes drooling, vomiting, and diarrhoea. Ingesting the roots can cause more severe symptoms including heart rhythm abnormalities and seizures. Keep cyclamen on a high surface or in a room your pets can’t access, and clear fallen flowers and leaves regularly.

12. Euphorbia (including Poinsettia)

Poinsettias (Euphorbia pulcherrima) are the most famous member of this group in the UK context — millions are sold every December as Christmas decorations. The broader Euphorbia genus also includes many popular succulent-type houseplants such as Euphorbia trigona (African milk tree) and Euphorbia tirucalli (pencil cactus).

All euphorbias produce a white, milky latex sap that is a significant irritant. Skin contact can cause redness, itching, and blistering in both humans and animals. Eye contact with the sap is a medical emergency. Ingestion causes oral irritation, vomiting, and diarrhoea in pets. Poinsettias specifically have a somewhat overstated reputation for lethality — they’re unlikely to kill a pet unless a truly enormous amount is consumed — but they’ll certainly make cats and dogs unwell. Wear gloves when pruning or repotting any euphorbia.

Practical Steps to Keep Your Home Safe

Know Where to Put Your Plants

Height is your friend. Most toxic houseplants become far less of a concern when placed genuinely out of reach. That said, remember that cats can reach shelves that seem impossibly high, and trailing plants like pothos will eventually hang low enough for a dog or
toddler to investigate. If in doubt, choose a room that can be closed off, use sturdy wall-mounted shelves, or opt for hanging planters positioned well away from furniture that could be used as a launch point.

Teach Children Early

Young children are naturally curious and often explore by touching and tasting. Make it a house rule that leaves, flowers, berries and soil are never for eating or playing with. Even non-toxic plants can cause choking, tummy upsets or skin irritation, so it is worth encouraging careful habits from the start.

Be Sensible When Repotting and Pruning

Sap, broken stems and fallen leaves can all create hazards. Clear up trimmings straight away, especially with plants such as dieffenbachia, euphorbia and peace lily. Wash your hands after handling plants known to cause irritation, and consider wearing gloves if you have sensitive skin. It is also wise to keep plant food, pesticides and compost stored securely out of reach.

Know What to Do in an Emergency

If you think your child or pet has chewed a toxic plant, remove any remaining plant material from the mouth and keep a sample or photograph of the plant for identification. For pets, contact your vet promptly; for children, call NHS 111 for advice, or 999 if there are severe symptoms such as breathing difficulties, seizures or collapse. Do not try to make anyone vomit unless specifically told to do so by a medical professional.

Safer Alternatives to Consider

If you share your home with inquisitive cats, dogs or small children, it may be easier to choose plants with a lower risk profile. Spider plants, calatheas, parlour palms, areca palms and many ferns are often popular options for pet-friendly homes. You can still create a lush indoor jungle without relying on species known for toxic sap, irritating crystals or poisonous berries.

Houseplants bring colour, calm and character to a home, but it is always worth balancing beauty with safety. By knowing which popular plants can cause problems, placing them carefully and acting quickly if an accident happens, you can enjoy your indoor garden with far greater peace of mind. A little caution goes a long way in keeping both pets and children safe in UK homes.