Yes, tomato plants are toxic to dogs, but the risk depends on which part your dog ate

The leaves, stems, and unripe green tomatoes on a tomato plant contain a compound called solanine, which is poisonous to dogs. Ripe red tomatoes are generally safe in small amounts, but the plant itself—especially the green parts—can cause stomach upset, lethargy, and in severe cases, tremors or heart problems. A dog would need to eat a large quantity of the plant material to suffer serious poisoning, but even a few leaves or green tomatoes can trigger mild symptoms.

The danger is highest when dogs chew on tomato plants in a garden or eat unripe tomatoes they find on the ground. Puppies and small dogs are at greater risk because they need less plant material to show symptoms. If your dog has access to tomato plants, the safest approach is to fence off the garden or keep potted plants out of reach entirely.

Key Takeaways

  • Tomato plant leaves, stems, and unripe green tomatoes contain solanine, a toxic compound that can poison dogs.
  • Ripe red tomatoes are safe for dogs in small amounts, but the green parts of the plant are always dangerous.
  • Symptoms of tomato plant poisoning include vomiting, diarrhea, drooling, lethargy, and loss of appetite.
  • Prevent poisoning by keeping tomato plants fenced off, using raised beds, or growing them in areas your dog cannot reach.
  • If your dog eats tomato plant material, contact your veterinarian or poison control right away, even if symptoms have not appeared yet.

Which parts of the tomato plant are poisonous

The leaves and stems are the most dangerous parts. These contain the highest concentration of solanine and are what dogs are most likely to chew on when they dig in a garden or brush against a plant. Even a few leaves can cause mild symptoms in a small dog.

Unripe green tomatoes are also toxic because they contain solanine before the fruit ripens. Once a tomato turns red and is fully ripe, the solanine breaks down and the fruit becomes safe. However, a dog would still need to eat a significant amount of ripe tomato to cause serious harm—a bite or two is unlikely to trigger poisoning.

The roots and soil around tomato plants are not inherently toxic, but they may contain pesticides or fertilizers that are dangerous. If you use any chemicals on your tomato plants, keep your dog away from the entire plant and the surrounding area.

Symptoms of tomato plant poisoning in dogs

Mild poisoning usually appears within a few hours of eating tomato plant material. Watch for vomiting, diarrhea, drooling, and loss of appetite. Your dog may also seem lethargic or restless, and may refuse to eat or drink normally.

More serious poisoning—which requires eating a large amount of plant material—can cause tremors, weakness, a slow heart rate, or difficulty breathing. These symptoms are rare in dogs that eat only a small amount of leaves or a few green tomatoes, but they can develop if a dog has eaten a substantial portion of the plant.

Symptoms typically peak within 24 hours and often resolve on their own within a few days if the dog received no treatment. However, you should still contact your veterinarian as soon as you realize your dog has eaten tomato plant material, because a vet can monitor your dog and provide supportive care if needed.

What to do if your dog eats tomato plant material

Call your veterinarian or an animal poison control center right away. Have the following information ready: your dog's weight, what part of the plant your dog ate (leaves, stems, or green tomatoes), how much your dog ate if you can estimate it, and when it happened. Do not wait for symptoms to appear—some dogs show no signs for several hours, and early contact with a vet is always safer.

Your vet may recommend bringing your dog in for an examination, or they may advise you to monitor your dog at home and call back if symptoms develop. If your dog is vomiting or having diarrhea, make sure fresh water is available and watch for signs of dehydration. Do not induce vomiting unless your vet specifically tells you to do so.

If you cannot reach your regular vet, call the ASPCA Animal Poison Control Center at (888) 426-4435 (a consultation fee applies) or the Pet Poison Helpline at (855) 764-7661. Both services are available 24 hours a day and can give you when ready guidance based on your dog's specific situation.

How to keep your dog safe from tomato plants

The simplest solution is to keep tomato plants out of your dog's reach. If you grow tomatoes in a garden, fence off the garden area so your dog cannot wander in and chew on plants or eat fallen fruit. A straightforward dog gate or garden fence does not need to be tall—it just needs to prevent casual access.

If you grow tomatoes in pots, place them on a high shelf, a patio table, or a raised surface your dog cannot jump onto or knock over. Hanging baskets work well for this reason. Make sure the pot is stable and will not tip if your dog brushes against it.

Raised garden beds are safer than ground-level gardens because they are harder for dogs to access, though a determined dog can still dig into them. If you use raised beds, consider adding a low fence or barrier around the bed itself. Remove fallen tomatoes and plant debris from the ground regularly, since dogs may eat these even if they cannot reach the living plant.

If you use pesticides, herbicides, or fertilizers on your tomato plants, keep your dog away from the entire area for the time specified on the product label. These chemicals add another layer of risk beyond the solanine in the plant itself.

Ripe tomatoes versus the plant: what is actually safe

A ripe, red tomato that your dog eats from your kitchen counter is not poisonous. Dogs can eat small amounts of ripe tomato without harm—a few bites or a small slice is fine. However, ripe tomatoes are high in acid and can cause stomach upset if your dog eats too much, so they should not be a regular part of your dog's diet.

The danger is in the plant itself, not the fruit once it is ripe. This is why a dog that eats a ripe tomato from your kitchen is at low risk, but a dog that chews on tomato plant leaves in the garden is at real risk. If your dog has eaten ripe tomato and is showing no symptoms, there is no need to contact a vet. If your dog has eaten any part of the plant—leaves, stems, or green tomatoes—contact a vet when ready.

Other plants in the nightshade family that are also toxic to dogs

Tomato plants belong to the nightshade family, and several other common plants in this family are also toxic to dogs. Potatoes (especially green or sprouting potatoes), eggplants, and peppers all contain solanine and should be kept away from dogs. Ripe potato flesh is safe, but green potatoes and potato plants are dangerous, just like green tomatoes.

Tobacco plants and deadly nightshade are also in this family and are highly toxic. If you grow any of these plants, explore the same safety rules: fence off the garden, use raised beds or high shelves, and keep your dog away from all plant material and fallen fruit.

Frequently Asked Questions

Can a dog die from eating tomato plant leaves?

Death is extremely rare. A dog would need to eat a very large amount of tomato plant material to suffer fatal poisoning. Most dogs that eat a few leaves or a small amount of plant material recover completely with no treatment. However, any ingestion of tomato plant material should be reported to a vet because symptoms can develop over hours and a vet can monitor your dog.

How much tomato plant is toxic to a dog?

There is no exact safe amount—toxicity depends on your dog's size, the part of the plant eaten, and the dog's individual sensitivity. A small dog eating a few leaves may show symptoms, while a large dog eating the same amount might show none. Always assume any amount of plant material is risky and contact a vet.

What if my dog ate one green tomato?

One green tomato is unlikely to cause serious poisoning, but it can still trigger mild symptoms like vomiting or diarrhea. Contact your vet or poison control to report what happened. They can tell you whether your dog needs to be seen or if monitoring at home is safe. Do not assume no symptoms means no poisoning—some dogs take hours to show signs.

Are tomato seeds poisonous to dogs?

Tomato seeds themselves are not toxic, but they are usually found inside ripe tomatoes, which are safe in small amounts. If your dog has eaten seeds from a ripe tomato, there is no need to worry. Seeds from green tomatoes are a different matter—avoid them because they come with the toxic fruit.

Can dogs eat tomato sauce or ketchup?

Tomato sauce and ketchup are made from ripe tomatoes, so they are not toxic because of the tomato itself. However, both products contain added salt, sugar, and sometimes garlic or onions, which can upset a dog's stomach or be harmful in large amounts. It is best to keep these products away from your dog.