Toxic Plants for Pets: A UK Guide
The UK's gardens, parks, woodlands, and homes contain many plants that can seriously harm pets. Some cause gastrointestinal upset; others can trigger heart arrhythmias, kidney failure, or rapid death. Many toxic plants are common, familiar garden species — which is why knowing which plants are dangerous is so important for pet owners. This guide covers the most significant toxic plants for dogs, cats, and other pets in the UK.
Lilies — Extremely Dangerous for Cats
True lilies (Lilium species) and day lilies (Hemerocallis species) are extremely toxic to cats and can cause fatal kidney failure. Every part of the plant is dangerous — the petals, leaves, stem, pollen, and even the water from a vase containing lilies. A cat that brushes against a lily and then grooms pollen from its fur can be poisoned.
Symptoms include vomiting, lethargy, and loss of appetite within a few hours, progressing to kidney failure within 24–72 hours if untreated. Lily toxicity is a veterinary emergency. Lilies are common in cut flower arrangements, particularly Easter bouquets — if you have cats, it is safest to avoid having lilies in your home entirely.
Foxglove (Digitalis)
Foxglove contains cardiac glycosides that affect the heart muscle. It grows widely across UK woodlands, hedgerows, gardens, and roadside verges. All parts of the plant are toxic. Symptoms of foxglove poisoning include vomiting, diarrhoea, drooling, lethargy, and — in more severe cases — irregular heartbeat, collapse, and death. Dogs that eat foxglove leaves or flowers on walks are particularly at risk. Contact your vet immediately if you suspect your pet has eaten any part of a foxglove plant.
Yew (Taxus)
Yew is one of the most poisonous plants in the UK. The entire plant — including the red berries (arils), leaves, bark, and seeds — contains alkaloids called taxines that disrupt heart and nervous system function. Yew trees are extremely common in UK churchyards, formal gardens, and as garden hedging. Even a small amount of yew can be fatal very rapidly. If you see your dog or cat chewing yew, treat it as an emergency and contact your vet immediately.
Rhododendron and Azalea
Rhododendrons and azaleas contain grayanotoxins that interfere with sodium channels in cell membranes, affecting the heart and nervous system. Symptoms include vomiting, excessive drooling, diarrhoea, weakness, ataxia (loss of coordination), low blood pressure, abnormal heart rhythm, and in severe cases, coma. Both shrubs are commonly found in UK gardens and parks, with flowering typically from spring through early summer.
Daffodils and Narcissus
All parts of daffodils are toxic to dogs and cats, particularly the bulbs, which contain the highest concentration of alkaloids including lycorine. Ingestion causes vomiting, diarrhoea, salivation, and — with significant quantities — more severe reactions including low blood pressure, tremors, and cardiac arrhythmias. The water in a vase containing daffodils should also be considered potentially toxic. Daffodils are very commonly planted in UK gardens and parks and are prolific in spring.
Autumn Crocus (Colchicum)
The autumn crocus (Colchicum autumnale) is distinct from the spring crocus and is highly toxic. It contains colchicine, which interferes with cell division throughout the body. Signs of poisoning include severe vomiting and diarrhoea (sometimes bloody), kidney and liver damage, respiratory failure, and in severe cases, death. Unlike the true crocus (spring), which causes mainly gastrointestinal irritation, autumn crocus poisoning is very serious and requires urgent veterinary treatment.
Ivy (Hedera helix)
Common English ivy causes irritation to the skin and mucous membranes on contact, and gastrointestinal upset — including vomiting, diarrhoea, and abdominal pain — if eaten. The berries and leaves are the most toxic parts. While ivy toxicity is generally less severe than that of yew or lilies, it should still be kept out of reach of pets and veterinary advice sought if significant quantities are eaten.
Ragwort (Jacobaea vulgaris)
Ragwort is particularly relevant for horses, other equines, donkeys, and rabbits. It contains pyrrolizidine alkaloids that cause cumulative, irreversible liver damage. Animals do not typically eat fresh ragwort willingly because it tastes bitter, but they will eat it when it is dried (for example in hay), when they are very hungry, or in some unusual cases when young animals are not deterred by the taste. Ragwort is a legally notifiable weed in certain contexts in the UK and must be controlled on land used for livestock.