Daylily
Hemerocallis graminea
Daylilies are not true lilies botanically, but they are equally deadly to cats — every part causes acute kidney failure. The "it is not a real lily so it must be safe" idea is dangerously wrong. Treat any exposure as an emergency.
Plate IHemerocallis — the daylily. Not a true lily, yet every part carries the same renal toxin that kills cats.
Three plants that look the part, without the risk.
No lily — true or "day" — is safe for cats. These flowering plants are ASPCA non-toxic and carry no renal toxin.
Orchid
Elegant, long-lasting blooms for a tabletop with none of the lily toxin.
Rose
A safe cut flower for cat households — strip the thorns and skip floral preservatives in the water.
Gerbera Daisy
Bright, cheerful blooms that are ASPCA non-toxic — a safe stand-in for a summer bouquet.
What it does to a cat.
If your cat has eaten any part of this plant, call ASPCA Poison Control (888) 426-4435 NOW. Do not wait for symptoms. Daylilies are among the deadliest plants for cats — just as dangerous as true lilies. Our step-by-step emergency plan walks you through the critical first hour.
Yes — daylily (Hemerocallis graminea, and Hemerocallis species generally) is toxic to cats. The ASPCA states: "Vomiting, inappetence, lethargy, kidney failure, and death is possible. Cats are only species known to be affected."
The dangerous "not a real lily" myth
Here is the correction that saves cats' lives: daylilies ARE NOT true lilies (Lilium) botanically, but they ARE equally deadly to cats.
People reason that because a daylily is not a "real" lily, it must be harmless. That reasoning is wrong and it kills cats. Hemerocallis contains the same kind of kidney toxin as true lilies, and a cat that ingests it can die of acute renal failure within days.
The ASPCA classifies Hemerocallis under the family Liliaceae for historical reasons. Modern botanists place daylilies in a separate family, Asphodelaceae — they are not in the genus Lilium at all. None of that taxonomy matters at the food bowl: the verdict is the same. Deadly.
Why daylilies are deadly
The toxin is specifically nephrotoxic to cats — it attacks the kidneys. After ingestion, cats can develop acute renal failure within 24 to 72 hours, and without prompt veterinary treatment mortality approaches 100 percent. Dogs and other species do not suffer the same injury; cats are uniquely vulnerable.
There is no established safe dose. Fatal poisonings have followed a few bites of leaf or flower, a small amount of pollen, or a sip of vase water.
Every part — and the water — is dangerous
- Pollen — picked up on the coat and swallowed during grooming.
- Vase water — water from a daylily arrangement concentrates the toxin.
- Leaves and flowers — the strap-like leaves are within reach of an indoor cat; the blooms attract curiosity.
What to do right now
- Call ASPCA Animal Poison Control at (888) 426-4435 or your veterinarian immediately.
- Do not induce vomiting unless directed by a professional.
- Wash any visible pollen from your cat's fur.
- Bring the plant or a photo to confirm the species.
See our full emergency guide for a cat that ate a lily for what happens at the clinic.
Safe alternatives
Avoid all lilies — Lilium and Hemerocallis alike. Safe, ASPCA-listed flowers include orchids, roses, and gerbera daisies. For an overview of which "lilies" are and are not dangerous, see our general lily guide and the deadly tiger lily page.
What we have actually seen.
Acute renal (kidney) failure
Despite not being a true lily, Hemerocallis causes the same fatal kidney injury as Lilium. Acute renal failure develops within 24 to 72 hours; untreated, mortality approaches 100 percent.
Early vomiting, inappetence, lethargy
Per the ASPCA — vomiting, inappetence, lethargy, kidney failure, and death is possible. Cats are the only species known to be affected.
Pollen on the coat
As with true lilies, pollen groomed from the fur is enough to poison a cat. No chewing of the plant is required.
Vase and cut-flower water
Daylilies are common in summer bouquets. Water from the arrangement concentrates the toxin and is dangerous if a cat drinks it.
- ASPCA Animal Poison Control Center. Toxic and Non-Toxic Plants: Orange Day Lily.Accessed June 2026 · aspca.org
- Pet Poison Helpline. Lily Toxicosis in Cats.Clinical brief · 2024 ed.