ASK THE OMBUDSMAN
Are Daylilies Poisonous?
By Donna Peck – AHS Ombudsman
QUESTIONS:
1. Are daylilies toxic to cats? I have even asked my vet and he thinks they are toxic
due to the fact that they are lilies (which they are not). My new cat loves the
foliage and I’ve read information both ways on this subject.
2. I have been trying to find out if daylilies are dangerous to cats. I am preparing to
plant several daylilies in my flower area and these are new to me. I have one cat
that just loves to nibble on plant leaves and I am concerned.
3. I wanted to plant some daylilies in a corner of my yard where corner posts are for
our house pasture. Are daylilies poisonous to horses? Also deer are a problem
here. They seemed to love my daylilies last year and they ate them up!
RESPONSES: These are just examples of the many questions I’ve received about the
toxicity of daylilies to animals. I also have received many answers. I’ve included a
few interesting ones, and will let you decide which you agree with.
1. No, daylilies are not toxic to cats. Our cat has to be forcibly removed from daylily
clumps anytime she got out in the yard. She loved them and they never harmed
her. (Eloise Koonce- Ombudsman committee member from Arizona)
2. .We have a commercial daylily nursery in Northern California with about four
acres of daylilies. We also have two beloved cats. Both have been with us for
twelve years. My cats occasionally eat a bit of grass for their digestion, but I’ve
never actually seen them eating daylily foliage. But if they did eat the foliage,
I’m sure that it would not affect them in the least. The daylily happens to be a
totally non-toxic plant. They are neither toxic to humans nor any creatures. As
you probably know, that is not necessarily the case with bearded iris or true lilies.
The only word of caution I can think of is if you use a toxic spray or bait. that has
toxic chemicals you put on the foliage and the cat happens to eat that very same
foliage, than of course the cat would ingest poison. The same with pools of water
that have run off the daylily foliage. I think the safest would be just to make sure
any chemicals you use are bird and animal friendly. (Bill Maryott from Maryott’s
gardens in California)
3. Daylilies are very non-toxic. One can eat the whole thing. However, true lilies are
toxic – especially in the oriental varieties. We have two cats that come into the
garden each morning to watch their “daddy” work. They both munch on the
daylily foliage without any problems. (Greg Bogard on the Robin-from WinstonSalem)
4. We leave the wheelbarrow filled with water in the last few weeks of May. After a
couple of weeks tadpoles appear from tree frogs. I take daylily blooms and place
them in the water every morning. The frogs feed on them until they crawl out and
hop away after a month. I place Clorox in the water to prevent mosquito larvae.
This does not seem to bother the frogs. I am sure the daylily is not toxic(Emma
Chandler from the Robin - Wellington, Tennessee)
5. As a member of AHS for decades, I do not recall any observation that any parts of
any types of daylilies are harmful to people and someone surely would have
commented by now if hey were. However, I had seen remarks that
daylilies…were addictive but I don’t recall that was observed because they were
eaten. I have heard someone say that a daylily was so beautiful, it left them
speechless, but speechlessness is very rare disorder among daylily growers, very
rare indeed. (Steve Morrison from the Robin – Silver Springs MD)
Because of the varied opinions, Donna sent this question to Pat Loveland who is
chair of the Scientific committee. And Pat sent it to the members of her committee.
This is their response:
A few years ago, daylily growers were dismayed by a report the ingested daylily
plants were reported to be toxic to cats. The ASPGA currently lists daylily in its
database of toxic plants. Linda Sue Barnes has been trying to get more information
about the basis for this listing. Linda Samples has been corresponding with Dr.
Wisner, whose credentials include not only being a Master Gardener but also works
the poison control service of the ASPCA. According to Dr. Wiener:
“Owners of ill cats who were exhibiting signs of renal toxicity have identified
[ingestion of] named daylilies, namely H. Stella D’ Oro. A university in Michigan is
currently working to actually identifying the toxin which is a water soluble complex
sugar. It is closely related to toxin in grapes and raisins that affects dogs. It will not
cause renal toxicity in “all” dogs and at present they cannot explain why. However if
the dog displays any signs of toxicity is not aggressively treated within 18 hours, it
will die. The toxin affects the proximal renal tubules which in the process of shedding
dead cells clogs the kidneys causing anurea. (the absence of urine production) and the
animal dies. The same toxin from daylilies in cattle can cause blindness – but again,
not in every instance. The selective nature of the toxicity in cats may be why our
members the have had cats that munched on foliage or flowers and not become ill are
raising questions. This toxin is specific for the feline and bovine species (at this time).
However, I must continue to warn those with cats that ingesting of daylilies could be
fatal to their pets. It’s all in the timing, though. Vomiting will occur within 2-3 hours
and if this is noted and the cat is taken to a veterinary clinic within 18 hours from
ingestion and treated aggressively they may be fine. If they become toxic and are not
aggressively treated with the time frame they will die.
Sorry for this news, but the vet with whom Linda Sample spoke was very credible
and our veterinary community respects the views of these practitioners who have
saved so many lives on 24/7 time frame.
If any AHS member has more information on this subject please let me know.
I think we should be informed about any new developments.
Email me (Donna Peck) at ombudsman@daylilies.org