Is it toxic to dogs?
Begonias
Begonia spp. · Begoniaceae
Also called Rex begonia, Mapleleaf begonia, Iron cross begonia, Peace begonia
Toxic to dogs
Severity: Mild
Yes. The ASPCA lists begonias as toxic to dogs. The underground parts are the most toxic, and the usual result is vomiting and drooling.
- Toxic parts
- Tubers and roots (most toxic), Leaves, stems and flowers
- Toxic compounds
- Soluble calcium oxalates
- Where you’ll find it
- House and garden
Signs of poisoning
- Vomiting
- Drooling (salivation)
- Mouth irritation
- Trouble swallowing
Why it’s harmful to dogs
Begonias are the colorful bedding and basket plants that thrive in shade, and the patterned rex types are houseplant favorites. The genus is enormous, with over a thousand species and thousands of hybrids, and the ASPCA lists the begonia group as toxic to dogs.
The ASPCA names soluble calcium oxalates as the toxic principle and says vomiting and drooling are the signs in dogs, with the underground portion being the most toxic. It lists kidney failure for grazing animals, not for dogs. The AKC notes mouth irritation and trouble swallowing.
The Merck Veterinary Manual adds that very large amounts of soluble-oxalate plants in general can lower blood calcium and damage the kidneys. A dog that digs up and chews tubers is therefore the case to watch.
If your dog ate begonias
Clear any plant bits from your dog's mouth and keep them away from the pot or bed. Watch for drooling, vomiting and trouble swallowing.
Call your vet, or ASPCA Animal Poison Control at (888) 426-4435 or Pet Poison Helpline at (855) 764-7661 (US; fees may apply), if your dog ate tubers or roots, ate a large amount, keeps vomiting, or seems weak. Outside the US, call your local emergency vet. Don't try to make your dog vomit at home. Note the begonia type, the part eaten, and when it happened.
Keeping your dog safe
Hang begonia baskets high and keep pots on shelves that your dog can't reach. In garden beds, fence or cage plantings, and don't leave dogs alone with freshly dug tubers or bulbs.
For shade-friendly color, African violets indoors and petunias outdoors are pet-safer choices. Reinforce "leave it" around pots and beds, and tidy up spent tubers after the season so nothing is left to dig up.
Dog-safe alternatives
Frequently asked questions
Which part of the begonia is most toxic?
The ASPCA says the most toxic part is underground, so tubers and roots are the biggest concern.
Is rex begonia toxic to dogs?
Yes. The ASPCA lists rex, peace, mapleleaf, iron cross and other begonias as toxic to dogs.
Can begonias cause kidney failure in dogs?
The ASPCA lists kidney failure for grazing animals. For dogs it lists vomiting and drooling. Call your vet if your dog ate a lot of tuber material.
Written from veterinary sources by the Pawsplained editorial team. Not yet reviewed by a veterinarian; this is general information, not a diagnosis or treatment plan. Updated Oct 30, 2026. Editorial policy