Are Hydrangeas Poisonous to Cats? Learn How to Keep Your Furball Safe
No matter how lovely hydrangeas look in your garden or as a bouquet, keep your curious kitty away. 
Tracey L. Kelley headshot By Tracey L. Kelley July 14, 2022 Advertisement Pin FB More Tweet Email Send Text Message Print 
cat near hydrangeas; are hydrangeas poisonous to cats? Credit: Helaine Weide / Getty
On This Page
- Are Hydrangeas Safe for Cats?
- How Do Cats Get Hydrangea Poisoning?
- Symptoms and Treatment
- How to Prevent Hydrangea Poisoning
Whether you have an adventure cat who roams the wilds of your backyard or a curious kitty on the countertop, not every plant is for feline consumption. While there are many plants safe for cats, numerous others are not.
So are hydrangeas poisonous to cats? It's important to know before you start landscaping or bring home a bouquet from the farmers' market. Here's what Michelle Burch, DVM with SafeHounds Pet Insurance has to say.
Are Hydrangeas Safe for Cats?
To put it simply: no. If you want to plant blooming hydrangeas in your garden, you have to keep a watchful eye over your cat. The flowers, leaves, buds, and stalks all contain amygdalin, but buds and young leaves have a higher concentration. Cats become ill by eating any part of the hydrangea plant.
RELATED: 16 Houseplants to Avoid if You Have Cats
How Do Cats Get Hydrangea Poisoning?
There are approximately 260 varieties of Hydrangeaceae species, including woody vines, shrubs, ornamental trees, and herbs. The toxic component of the hydrangea is called amygdalin. When ingested by any mammal and metabolized, it converts to dangerous cyanide.
Fortunately, hydrangea poisoning is rare, as a kitty would have to eat quite a bit of the plant to be seriously affected.
Symptoms and Treatment of Hydrangea Poisoning in Cats
Burch says the most common symptoms of hydrangea poisoning in cats include:
- Loss of appetite
- Lethargy
- Vomiting
- Diarrhea
- Stomach pain
If your kitty was sniffing around hydrangeas, symptoms usually appear in as little as 30 minutes, alerting you that they've nibbled on the plant.
Whisk your pet to the veterinarian immediately, and take parts of the plant along so the vet can correctly identify it and know what to test for and how to administer treatment. To remove the toxins and stabilize your kitty's condition, your vet might need to induce vomiting, provide intravenous fluids, and prescribe medication. The exam could also require some bloodwork, a urine test, and X-rays to confirm the kitty's organ function is normal and there aren't any other digestive issues.
Once you're back home, it's a good idea to follow a bland diet for a couple of days to help ease digestion. A handy go-to is unseasoned boiled chicken or turkey mixed with cooked white rice.
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How to Prevent Hydrangea Poisoning
Because hydrangeas are poisonous for dogs, too, take good care of your animal friends by changing the dynamics of your landscape.
If you already have hydrangeas in the yard where kitty wanders, make access to the plants more difficult. "Place shells, branches, and thorny vines, which aren't appealing for a dog or cat to step on," Burch says.
She also recommends applying non-toxic botanical oil sprays around the edges of the plants, as these products have a noxious smell to animals. Cats in particular aren't fans of citrus, so dilute grapefruit, lemon, lime, or orange juice in water for a quick and easy spritz, or consider a commercial product such as Four Paws Bitter Lime Deterrent Spray. Motion-activated sprinklers and ultrasonic deterrents are sometimes helpful, too.
However, the most effective hydrangea poison prevention is to keep cats indoors (which is best for their overall health) or inside a catio. That is, unless you plan on training them to walk on a leash and harness for (supervised) exploration!
RELATED: Why Cats Eat Grass and How to Satisfy Their Appetite Indoors
Additional reporting by Jennifer Nelson.
