What should I do if my cat ate Smooth Hydrangea?

Call immediately if your cat shows weakness, panting, or bright red gums (possible cyanide effect). For mild GI signs, call if vomiting or diarrhea continues past a few hours, especially in kittens or seniors who can dehydrate quickly.

What should I do if my dog ate Smooth Hydrangea?

Call immediately if you see weakness, bright red gums, panting, or rapid breathing — those can signal cyanide effect after a large dose. For mild GI signs, call if vomiting or diarrhea persists past a few hours or your dog can't keep water down.

Smooth Hydrangea — (c) Douglas Goldman, some rights reserved (CC BY-SA), uploaded by Douglas Goldman — Photo by (c) Douglas Goldman, some rights reserved (CC BY-SA), uploaded by Douglas GoldmaniNaturalistCC BY-SA

Photo by (c) Douglas Goldman, some rights reserved (CC BY-SA), uploaded by Douglas GoldmaniNaturalistCC BY-SA

Pet safety reference

Smooth Hydrangea

Q: Is Smooth Hydrangea safe for cats?

Smooth Hydrangea is potentially toxic to cats. Ingestion can lead to gastrointestinal upset. Please contact your veterinarian or a pet poison control center if you suspect your cat has consumed any part of this plant.

Q: Is Smooth Hydrangea safe for dogs?

Smooth Hydrangea is potentially toxic to dogs. While usually mild, ingestion can cause significant digestive irritation. Always consult a veterinarian if your dog shows signs of illness after exposure.

Hydrangea arborescens

Hydrangea arborescens is a deciduous shrub known for its large, rounded clusters of white flowers. It contains cyanogenic glycosides which can cause gastrointestinal distress if ingested by pets.

Check a list

Hills of SnowHydrangea arborescensSmooth HydrangeaWild Hydrangea

Light: Partial shade to full sun
Habit: Deciduous shrub
Care: Moderate

Safety status

Cats & Dogs

Potentially toxic

Consulted references classify the plant as toxic or irritating for that pet type.

Verified against ASPCA/provenance audit 2026-05-06 on May 6, 2026.

Sources

ASPCA Toxic Plant List

If a pet has chewed or swallowed plant material and is showing symptoms, contact a veterinarian or poison resource immediately. This product is for structured reference, not diagnosis.

Cats — concern notes

Common signs

Vomiting, diarrhea, lethargy, and potential abdominal pain.

Escalation note

Ingestion can lead to gastrointestinal upset. Please contact your veterinarian or a pet poison control center if you suspect your cat has consumed any part of this plant.

Dogs — concern notes

Common signs

Vomiting, diarrhea, increased heart rate, and potential depression.

Escalation note

While usually mild, ingestion can cause significant digestive irritation. Always consult a veterinarian if your dog shows signs of illness after exposure.

Safer alternatives

No hand-picked alternatives for this plant yet. You can still pick your own using the Compare button on any other plant.

Source evidence

ASPCA Toxic Plant List

toxicology · 99% reliability

Open source

Hydrangea arborescens is listed as toxic to both cats and dogs due to the presence of cyanogenic glycosides.

NC State Extension Plant Toolbox

botanical · 94% reliability

Open source

Hydrangea arborescens is a native shrub that is toxic if ingested by humans and pets.

cats safety page My cat ate Smooth Hydrangea dogs safety page My dog ate Smooth Hydrangea

Same safety verdict

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