Hydrangea
CautionHydrangea contains a cyanogenic glycoside, but the ASPCA notes that cyanide intoxication is rare and it usually produces gastrointestinal upset instead. Large ingestions still cause vomiting and diarrhea.
This food guide has not been reviewed by a veterinarian. It summarises general information from sources and should not be used to decide whether a food is suitable for an individual dog or to assess an emergency.
Check before feeding
Check the precautions before sharing
Risk depends on preparation, ingredients or amount. Read the precautions below; body weight alone cannot establish a safe portion.
Signs and health concerns
This list includes both observable signs and conditions identified through examination or testing. It cannot establish the cause or whether an exposure is safe.
- Vomiting
- Diarrhoea
- Reduced activity and responsiveness
- Loss of appetite
- Lethargy
- Dehydration
More about this food
Hydrangea's toxic principle is a cyanogenic glycoside, which sounds alarming until you read what the ASPCA actually says. The entry lists hydrangea as toxic to dogs, then gives the clinical signs as "vomiting, depression, diarrhea. Cyanide intoxication is rare - usually produces more of a gastrointestinal disturbance." The theoretical hazard and the practical one are not the same here.
What usually happens is this. A dog chews leaves, flowers or buds, and within a few hours you get vomiting and loose stool or diarrhea, often with a dip in appetite and energy. Most dogs are back to normal in a day or two. The exception is volume: a dog that works through a whole shrub can vomit and scour enough to become dehydrated, and a small dog reaches that point on much less plant. Buds and young leaves are reported to carry more of the glycoside, so a shrub in bloom deserves a bit more attention.
In the US, hydrangeas are a foundation-planting staple in the Northeast and Southeast, plus florist pots at Easter and Mother's Day. Gift pots often come with fertilizer spikes, aluminum sulfate used to push the blooms blue, and soil amendments, so if your dog ate potting soil along with the leaves, the additives are worth mentioning to your vet. Dried hydrangea in a wreath or arrangement is the same plant.
Move the plant, note what and how much and when, and call your veterinarian or the ASPCA Animal Poison Control Center at (888) 426-4435 if you are unsure. A couple of chewed leaves in a dog who seems normal can be watched at home with water available. Call without waiting if vomiting repeats, if there is blood in the stool, if your dog is lethargic or cannot keep water down, if the gums look pale, or if fertilizer and potting soil went down too. Do not induce vomiting at home; that decision and everything after it belongs to your veterinarian.
Frequently asked questions
- It contains cyanide. Should I be panicking?
- Probably not. The ASPCA states that cyanide intoxication from hydrangea is rare and that it usually produces gastrointestinal upset instead. Vomiting and diarrhea are the realistic outcomes; call your vet if they repeat or your dog goes flat.
- How much is too much?
- There is no published threshold. A few leaves in a dog acting normally can be monitored, but call now if she stripped a shrub, is vomiting repeatedly, or seems lethargic. If she also ate potting soil or fertilizer, get advice regardless of the amount.
- What about dried hydrangea in a wreath?
- It is the same plant and not safer for drying. Dried flowers and stems also break into swallowable pieces, so keep wreaths and arrangements where the dog cannot reach them.