What vegetables shouldn’t you feed your dog? Essential guide

Vegetables play a role in balanced canine nutrition, but not all vegetables are safe for dogs. Although dogs are omnivores who naturally eat both meat and plant matter, some vegetables can be harmful or toxic. Feeding your dog the wrong kind or parts of vegetables can cause serious health issues, so informed feeding is essential.

This guide reveals which vegetables should never be fed to your dog, why they pose risks, and how to safely include veggies in your dog's diet. Later, we'll share important tips on avoiding hidden dangers in human meals and snacks. This updated advice reflects the current veterinary consensus in the UK in 2025.

Understanding Why Some Vegetables Are Toxic to Dogs

Many vegetables that humans eat safely contain compounds that dogs cannot tolerate well. The most risky tend to be in the Allium family (onions, garlic, leeks, chives) as well as certain parts of plants like leaves or stems. Toxins in these vegetables can damage red blood cells, cause organ damage, or lead to digestive upset.

Veterinary experts advise complete avoidance of these vegetables and caution even with small amounts, as toxicity can develop over time or with larger quantities.

1. Allium Family: Onions, Garlic, Leeks, and Chives

Onions are toxic in all forms—raw, cooked, or powdered—and can cause a condition called haemolytic anaemia in dogs. This means their red blood cells break down, leading to weakness, pale gums, increased heart rate, and breathing difficulties.

This also applies to garlic, leeks, and chives, which contain similar toxic compounds called organosulphoxides. While some veterinary-approved supplements may include tiny amounts of garlic for health benefits, do not feed your dog raw garlic or foods containing garlic without vet guidance.

2. Rhubarb Leaves and Stalks

Rhubarb leaves and stalks contain oxalates and naturally occurring crystals that can interfere with calcium metabolism. If ingested, this can lead to calcium depletion, kidney problems, and potentially renal failure in acute cases.

Although toxicity is relatively rare, it is critical to keep rhubarb plants and any parts of them away from your dog.

3. Tomato Stems and Leaves

While ripe tomato fruit is generally safe in moderation, the green parts of the tomato plant—including stems and leaves—contain solanine. Solanine can cause gastrointestinal irritation, lethargy, and, in larger amounts, more severe poisoning symptoms.

Always remove all green tomato parts before allowing your dog near tomatoes.

4. Potato Plant Greens

Potato tubers themselves are safe if cooked and given plain, but the green parts of the potato plant, including leaves and stems, also contain solanine and are toxic to dogs.

Prevent your dog from chewing or eating any green potato plant parts, which can cause stomach upset and toxicity.

Beware of Hidden Dangers in Human Food

Table scraps or sauces often contain small amounts of onions, garlic, or other harmful vegetables that can build up toxic effects if consumed regularly. Even stews and casseroles may have ingredients unsafe for dogs.

Always be cautious when feeding any human food leftovers. If you suspect your dog has eaten a toxic vegetable, watch for symptoms like vomiting, diarrhoea, weakness, rapid breathing, or unusual behaviour and seek veterinary advice promptly.

How to Safely Include Vegetables in Your Dog’s Diet

Many vegetables are nutritious and beneficial for dogs, including carrots, peas, green beans, and pumpkin, when offered in appropriate amounts. Always introduce new foods gradually and consult your vet or a canine nutrition expert if you plan significant diet changes.

Feeding a complete, balanced commercial diet or veterinary-approved raw diet ensures your dog gets the necessary nutrients without exposure to harmful vegetables.

Additional Resources on Responsible Dog Care

When selecting a dog or puppy, consider adopting from reputable breeders or shelters that prioritise health and welfare, ensuring your pet’s lifelong wellbeing. Responsible feeding and care are central to a happy, healthy dog.

For those looking to find a puppy from trusted sources, reputable breeders offer puppies with documented health and welfare standards.

Find puppies from reputable breeders

Question: Can dogs eat spring onions safely?

Quick Answer: Dogs should not eat spring onions as they belong to the Allium family and can cause toxicity involving red blood cell damage.

Spring onions contain the same compounds as onions and garlic that can lead to haemolytic anaemia in dogs. Even small amounts can be harmful over time. It is safest to avoid feeding spring onions in any form to your dog.

Question: What to do if my dog has eaten toxic vegetables?

Quick Answer: Contact your vet immediately for advice. Early treatment can prevent serious complications.

If your dog ingests toxic vegetables such as onions or rhubarb leaves, monitor them closely and look for symptoms like vomiting, diarrhoea, weakness, or signs of pain. Your vet may recommend bringing your dog in for observation or treatment depending on the amount ingested and symptoms.

Never delay veterinary care as some symptoms can develop hours or days later but require prompt attention.

Conclusion

Feeding vegetables safely to your dog means avoiding toxic varieties like onions, garlic, leeks, rhubarb greens, tomato stems, and potato leaves. Awareness about hidden dangers in human food helps prevent accidental poisoning.

Providing healthy, vet-approved vegetable snacks and a balanced diet contributes to your dog’s wellbeing. Always seek veterinary guidance if uncertain about a food and choose trusted sources for your pet’s food and healthcare.