Is Mystery Gardenia toxic to cats?

Mildly. The ASPCA lists mystery gardenia as mildly toxic to cats — a chewing cat typically gets mouth irritation, drooling, and vomiting rather than a medical emergency, but it is still best kept out of reach. ASPCA explicitly lists Gardenia jasminoides as toxic to dogs, cats, and horses. Toxic principles are genioposide and gardenoside (iridoid glycosides), causing mild vomiting, diarrhoea, and hives. Symptoms are typically mild and self-limiting but seek veterinary advice if significant ingestion occurs.

ASPCA explicitly lists Gardenia jasminoides as toxic to dogs, cats, and horses. Toxic principles are genioposide and gardenoside (iridoid glycosides), causing mild vomiting, diarrhoea, and hives. Symptoms are typically mild and self-limiting but seek veterinary advice if significant ingestion occurs. Signs usually appear soon after chewing rather than hours later — watch for drooling, pawing at the mouth, vomiting, loss of appetite, or unusual lethargy after your cat has had access to mystery gardenia.

Stay calm. Remove any plant from your cat's mouth and take the plant away. Note how much was eaten and when, and do not induce vomiting unless told to. Call your vet or the ASPCA Animal Poison Control Center on (888) 426-4435 and follow their advice; a leaf or photo helps the vet treat it correctly.

The ASPCA classification Growli uses applies to both cats and dogs: Mystery Gardenia is mildly toxic to dogs as well. See the full mystery gardenia pet-safety guide for both species.

For a similar look without the risk, see the best cats-safe plants list — every plant there is ASPCA non-toxic to cats and dogs.