Poisonous Garden Plants: Iris, Azalea, Hydrangea

Updated on February 21, 2018
Gloriousconfusion profile image

I love gardening, garden design, learning gardening techniques & photographing & painting plants. Member of Royal Horticultural Society.

Are you aware that the iris, azalea and hydrangea are considered to be toxic plants?

Most people know about the very poisonous plants like mistletoe, deadly nightshade and poison ivy, but as a safety precaution, you should also know about other toxic plants like iris, azalea and hydrangea which might not necessarily kill, but could still poison someone and make them feel very ill.

Paradoxically, many potentially harmful plants, including Irises, are also considered to have healing properties.

Danger Alert! Iris, Azalea and Hydrangea are Poisonous Plants

Hydrangea and deaths head
Hydrangea and deaths head | Source

Be Aware of Which Plants are Poisonous



Poisonous Plant Iris at Chelsea Flower Show


Poisonous Plant: Iris (Flag)

The bulbs of irises are poisonous, possibly only mildly so.

Irises contain the potentially toxic compounds irisin, iridin, or irisine.

Poisonous Parts:

Bulb, leaves, and stem

Symptoms of Poisoning:

The gastrointestinal tract may become affected by the glycoside iridin, causing nausea, vomiting, abdominal pain, diarrhoea, and fever. Also Iris can cause skin irritation or dermatitis.

Medical Uses:

In ancient times Egyptians would grind together salt, small doses of dried iris, mint and pepper, to make a substance for cleaning the teeth. Recent research has shown that the iris really does have beneficial properties and a preparation made from iris is effective in combatting gum disease.

Poisonous Plant Azalia


Poisonous Plant: Azalea - Are Azaleas Poisonous to Humans? Yes They Are

Azaleas are a sub species of the Rhododendron family. Azaleas and Rhododendrons are ornamental shrubs, grown for their clusters of spectacularly bright and showy flowers and evergreen foliage.

They have potentially toxic leaves and flowers and even the honey from their flowers can be poisonous.

Poisonous Parts:

Flowers and leaves contain glycosides, but particularly andromedotoxin. This is a volatile resin which burns the mouth, and thus usually discourages potential victims from consuming dangerous quantities of the leaves.


The human digestive tract is capable of breaking down small doses of andromedotoxins into harmless compounds, so human fatalities from eating these plants are rare. However, victims who consume a lot suffer from nausea, vomiting, abdominal upset, and low blood pressure.

People who regularly eat affected honey may also suffer similar chronic symptoms .

Poisonous Hydrangea

Hydrangea Macrophylla - One of the Lacecap species
Hydrangea Macrophylla - One of the Lacecap species | Source

Poisonous Plant: Hydrangea (Hydrangea macrophylla) - Who Would Have Thought That Hydrangea is a Poisonous Plant?

Hydrangea (botanical name: Hydrangea macrophylla) is a plant which is poisonous to humans, although not usually deadly.

Poisonous Parts:

Leaves, buds, flowers, and bark.The poisonous component is Hydragin.


stomach pain, nausea, vomiting, sweating,diarrhoea,lethargy and, in severe cases, more serious problems like labored breathing, convulsions and coma.

Sensitive people may develop contact dermatitis from handling the plants.


Doctors will try to replace your fluids, help you breath more easily and administer drugs to bring back your normal heart rhythm.

Would you know what to do if a child or pet ate a poisonous plant?

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If you Have Irises, Azaleas or Hydrangeas in Your Garden, Don't Panic

I would just mention that I have all these plants in my garden, and have never experienced any adverse effects, and neither has my cat, or anyone I know.

So what can we conclude from this?

Have I been extra careful?

No - until I started researching, I had no idea that these plants were poisonous. I've been aware since I was a child that plants with white sap, like poinsettias, are poisonous, and I learned the hard way that hellebores are poisonous, but these particular beauties - never!

Have I just been lucky?

I will have to answer yes to that. So what do we put my good fortune down to?

All I can say is that I have planted them, touched them, nurtured them and even pruned them without developing any of the symptoms described above. Maybe some people are just more sensitive to noxious substances than I am.....and, of course, I always wash my hands after gardening, and I'm not inclined to lick my fingers or rub my eyes after touching any plants, whether or not I believe they are poisonous.

Has that saved me from being poisoned? Hard to say. But it does seem to be good advice generally.

Feedback - Do leave your Comment below - it's so nice to know what people are thinking

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    • Thelma Alberts profile image

      Thelma Alberts 2 months ago from Germany

      I didn´t know that these plants are poisonous. Thanks for the heads up.

    • Gloriousconfusion profile image

      Diana Grant 7 months ago from United Kingdom

      Sorry to hear that. I'm quite surprised, as I've grown masses of crocosmia (montbretia) for years, and have not had any bad experience. No doubt some people are more sensitive than others.

    • profile image

      Joan P 7 months ago

      I was recently pulling weeds in my garden and was scratched by the leaf of a crocosmia leafy and it burned my skin and it sent shivers down my left arm, I immediately tried was my skin off with cool water, this did nothing, so I tried antibacterial soap, then vinegar which seemed to work the best! After it still burning and tingling (not a nice tingle either)! I then tried aloe straight from the plant! After an hour it is less painful! I do have contact dermatitis but never anything like this!!!

    • profile image

      David 18 months ago

      I was born and raised in Savannah, GA. My siblings, my friends, and I ate azalea flowers all our childhood. Whenever we were hungry and outdoors, we'd pick azalea flowers and eat them like crazy. They are actually quite sweet and delicious!

    • profile image

      Amy 22 months ago

      I recently planted four Hydrangeas very close to my vegetables. I have no idea they are poisenous. Does anyone know if it is safe? I really appreciate your help.

      Thanks a lot!

    • erorantes profile image

      Ana Maria Orantes 2 years ago from Miami Florida

      I like your hub. Some plants are dangers. It is true. I am glad . you are making people aware of this beautiful poisenous flowers. I treat any flowers with causious because It is not easy to know. What, the plants and flowers can do to us. You did an exvellent job. I like the pictures. The information and orginization is good. Thank you miss gloriousconfusion for the information. Do not forget to check your subtittles.

    • profile image

      sandrawelch 2 years ago

      Very informative, thank you. I like to walk with my grandson, being four, he likes to touch every thing. Being a very sweet little boy, he always wants to pick flowers to take home to Mommy. I appreciate the list, and plan to use it.

    • Virginia Allain profile image

      Virginia Allain 2 years ago from Central Florida

      I had no idea that the hydrangea was a problem plant.

      Since I have no children around, I'll continue to cultivate it.

    • ecogranny profile image

      Kathryn Grace 3 years ago from San Francisco

      Thanks for the information. My 2-year-old granddaughter and I encounter hydrangeas frequently on our walks, so I am grateful to learn that all parts of the plant are poisonous. She asks me the name of almost every plant in her field of vision and increasingly shows interest in the different types and sizes of leaves.

      About the Egyptians using bits of the iris plant in their tooth care mixture, don't you always wonder how the ancients made these discoveries? I certainly do.

    • susanholland10 profile image

      Susan Holland 3 years ago from Southwest Missouri

      Interesting! I have the plants, and I never considered them poisonous.

      Thanks for sharing! Votes and shared! :-)

    • Brite-Ideas profile image

      Barbara Tremblay Cipak 3 years ago from Toronto, Canada

      I'm a little in the dark on what's toxic in the plant department, so I appreciate your page very much!

    • SandyMertens profile image

      Sandy Mertens 3 years ago from Frozen Tundra

      These flowers are very pretty. Interesting to find that they are poisonous.

    • Mary Crowther profile image

      Mary Crowther 3 years ago from Havre de Grace

      Glad to know this for when my grandchildren come to visit.

    • MelRootsNWrites profile image

      Melody Lassalle 3 years ago from California

      I can attest to the fact that hydrangea is poisonous. My sister brought one over in a basket. We didn't know it but a leaf fell off. About 15 minutes later my dog threw up. And, then she continued to do so for the next hour and a half. She did rid herself of all the pieces of leaf. And, she was fine a few hours later. It was sure scary though. I remember reading later that although it doesn't produce cyanide, it has cyanide like affects. It's usually not deadly, but boy, it sure gave my dog an upset stomach.

    • amandascloset0 profile image

      amandascloset0 3 years ago

      I have always kept hydrangea's and poinsettas around my house. I've had other poisonous plants but mostly those two. Because of this I have kept myself aware of what plants are poisonous and what to do if a child were to eat them. The best defense for me is making sure that children know if you put this in your mouth it will make you very sick and could kill you.

    • profile image

      GrammieOlivia 3 years ago

      Always good to know these kinds of things.

    • ramonabeckbritman profile image

      Ramona 4 years ago from Arkansas

      Very informative. Thank you. Your lens is lovely.

    • profile image

      burntchestnut 4 years ago

      We need to continuously teach our children about all plants; what to grow so they can have food, what to forage if they ever need to, and what plants are poisonous (including mushrooms).

    • blue22d profile image

      blue22d 4 years ago

      Oh bum! I love the blue iris - had no idea. Just recently visited The Getty Center in Los Angeles and in their garden they have azaleas - at the center - who would have known. Any cases of people dying from the normal garden usage? Most probably would not eat them - best not to have around little children. THANKS for the info.

    • profile image

      anonymous 4 years ago

      I have always liked hydrangea's, they are one of my favourite flowers, but I had no idea they were poisonous! Very informative lens.

    • profile image

      liny-tan 4 years ago

      this is an information to be kept always in my mind!

    • BLouw profile image

      Barbara Walton 4 years ago from France

      I trained as a Landscape Architect so had to know a little about which plants to use, and which plants to avoid. the poisonous plants came into the latter category, but I didn't know that any of these plants were poisonous.

    • Gypzeerose profile image

      Rose Jones 4 years ago

      This is important information, especially since my dog loves to chew up plants in the garden. Bookmarked so that others see this info.

    • profile image

      lionmom100 4 years ago

      I have almost all of the above in my garden. I try to plant some of our Pacific Northwest natives, many of which are not poisonous and have been used as food sources by Native Americans

    • Gloriousconfusion profile image

      Diana Grant 5 years ago from United Kingdom

      @hemantets: Yes, I have some beautiful artificial silk plants. Thanks for the info

    • profile image

      hemantets 5 years ago

      Really plants like iris, azalea and hydrangea are very dangerous for all, these are very toxic which is very bad for our body system. Here we can use artificial azalea and hydrangea plants, I think this website (www.qualitysilkplants.com) is helpful to purchase artificial azalea and hydrangea plants.

    • AgingIntoDisabi profile image

      AgingIntoDisabi 5 years ago

      Very ironic that some of the most pretty plants are poisonous. Thanks for letting us know.

    • profile image

      marsha32 5 years ago

      Irises are my favorite flowers. I wouldn't have ever known they are poisonous.

    • Gloriousconfusion profile image

      Diana Grant 5 years ago from United Kingdom

      @Lee Hansen: good one! Or how about Flowers to Die for?

    • Lee Hansen profile image

      Lee Hansen 5 years ago from Vermont

      Gives new meaning to the phrase Drop Dead Beautiful ...

    • profile image

      cmadden 5 years ago

      News to me!

    • Gloriousconfusion profile image

      Diana Grant 5 years ago from United Kingdom

      @Michey LM: Yes, it is surprising. The thing is, you can still grow them, but just be careful not to stay in contact with them for long, and be sure to wash your hands before you touch your mouth.

    • Michey LM profile image

      Michey LM 5 years ago

      I don't know that iris, azalea and hydrangea can be poisonous - it is a total surprise for me... especially because I like iris and azalea. thanks for shearing!

    • profile image

      wecomparebooks 5 years ago

      I learned a lot from this lens!

    • profile image

      wecomparebooks 5 years ago

      I learned a lot from this!

    • Craftypicks profile image

      Lori Green 5 years ago from Las Vegas

      I didn't kknow Iris was poisonous either. I tried to have a poison free yard when my kids were little. Oh well, at least they never ate them.

    • profile image

      anonymous 5 years ago

      I am enjoying your website. Did not know that the iris was poisonous. Just started planting them in the last couple of years. I will have to make myself wear gardening gloves now. Thanks for the info.

    • JohnCumbow profile image

      JohnCumbow 5 years ago

      Never realized I had all these toxic plants growing around my country garden. They're all so beautiful. Thanks for the heads-up!

    • profile image

      Helene-Malmsio 5 years ago

      Well well, I did not know that any of these three plants were poisonous - I really learned something useful today, thanks!

    • profile image

      burntchestnut 5 years ago

      I know quite a bit about poisonous plants because I love reading old mysteries like Agatha Christie.

    • kimark421 profile image

      kimark421 6 years ago

      Obviously I don't know my poisonous plants, I had no idea Iris and Azalea were on the list. Thank you!

    • profile image

      Ladyeaglefeather 6 years ago

      Great lens. Thanks for all the information. I didn't know, a lot of these plant were


    • knit1tat2 profile image

      knit1tat2 6 years ago

      nice and informative lens. Thanks!

    • profile image

      anonymous 6 years ago

      thanks for the informative lens!

    • hsschulte profile image

      hsschulte 6 years ago

      I have many of these growing outside. I will have to warn my kiddos. Thanks.

    • julescorriere profile image

      Jules Corriere 6 years ago from Jonesborough TN

      I never knew azaleas were poisonous. I did find out Wisteria is poisonous, after my nephew put a pod in his mouth and started to swell up. Thanks for this lens. It was sooo interesting!

    • KimGiancaterino profile image

      KimGiancaterino 6 years ago

      Thanks for this warning. I've never had success growing any of these plants, so maybe it was a blessing in disguise. My cats are forever munching on grasses, and I try to keep toxic plants out of the garden.

    • Optionstradingiq profile image

      Optionstradingiq 6 years ago

      Wow, I had no idea Azaleas and Hydrangeas were poisonous plants! Good to know.

    • sousababy profile image

      sousababy 6 years ago

      Wow, good to know. I'm not much of a gardener at all. Thanks for the education.

    • pheonix76 profile image

      pheonix76 6 years ago from WNY

      Thanks for this informative lens! I love all three of these plants, but never realized that iris were poisonous. :O I have many iris plants in my flower garden and there are plenty of Azaleas and Hydrangeas around my area. Thanks again for sharing!! (:

    • profile image

      Chardoo 6 years ago

      Both of these beautiful plants grow everywhere in the Puget Sound, Washington State area. My daughter has had to replant hers to the front yard for a nice street view and keep her three tiny dogs in the back yard where they have safe, edible plants.

    • ZenandChic profile image

      Patricia 6 years ago

      @Gloriousconfusion: Your welcome!

    • Gloriousconfusion profile image

      Diana Grant 6 years ago from United Kingdom

      @ZenandChic: Dangerous to eat flowers and leaves, and even the honey sourced from these plants. Thanks so much for the Angel Blessing!

    • ZenandChic profile image

      Patricia 6 years ago

      Are they dangerous to touch or eat? I just photographed both kinds of these flowers... Irises and Azaleas.

    • junecampbell profile image

      June Campbell 7 years ago from North Vancouver, BC, Canada

      I had no idea these three beautiful plants were poisonous. All three grow prolifically in Vancouver. It's good to know.

    • sukkran trichy profile image

      sukkran trichy 7 years ago from Trichy/Tamil Nadu

      thanks for the useful info.

    • profile image

      Craftybegonia 7 years ago

      That is a great warning to give. It would be horrible if one's pet gets killed by chewing on a toxic plant! They have beautiful flowers though...

    • PromptWriter profile image

      Moe Wood 7 years ago from Eastern Ontario

      I did not know hydrangeas were toxic. I have a few in the yard I'll have to make sure dog doesn't get into it.

    • profile image

      anonymous 7 years ago

      Toxic plants: I want to find out as much as I can about these plants. You see, we've got a very large garden/aboretum which would cost at least A$8,000 to fence,and then some native animals can get over/thru. fences. We've found that all our 'resident' native animals either are scared off some toxic plants straight away, or they eat a tiny bit and then stop straight away. That way we can have a great garden and enjoy seeing our animals come out at night to graze only on our lawn. (saves lawnmowing?)Knowing all we can about toxic garden plants ensures we and our animal friends live together. We come from Tasmania, Australia.

    • ICanCook profile image

      ICanCook 7 years ago

      I'm a gardener and I'd love anything from this site. I also didn't know Azaleia and Hydranga were poisonous. I have both in my garden. Thanks for the info.

    • dustytoes profile image

      dustytoes 7 years ago

      Nope, I sure didn't know that hydrangeas are poisonous, but when I work around Azaleas I always get an itchy rash. I enjoyed your informative lens and will lensroll.

    • profile image

      jamesraynor79 7 years ago

      Even though they are deadly, they are still very beautiful. If you are looking for beautiful, but deadly flowers, check out CanadaWideFlowers.com. You can shop flowers to your heart's content.

    • profile image

      tssfacts 7 years ago

      Great article. I knew that Hydrangea were but didn't know about the other two.

    • myneverboredhands profile image

      myneverboredhands 7 years ago

      Another great and informative lens. Thumbs up!

    • Gloriousconfusion profile image

      Diana Grant 7 years ago from United Kingdom

      @OhMe: Thank you so much for blessing - that was valuable information too!

    • Gloriousconfusion profile image

      Diana Grant 7 years ago from United Kingdom

      @Hairdresser007: Well, six months have passed since your stated intention to creat a lens on irises - how have you got on, and did you ever create an Iris Area?

      I'm not very good with irises - they seem to get overgrown by other plants, or eaten by slugs and squirrels, so only two flowered this year (but they were gorgeous!)

    • OhMe profile image

      Nancy Tate Hellams 7 years ago from Pendleton, SC

      Thank you for this valuable information on Poisonous Garden Plants. Blessed.

    • BarbRad profile image

      Barbara Radisavljevic 8 years ago from Templeton, CA

      Do you think irises are poisonous to gophers as well as to humans? I don't think my gophers have eaten any of mine yet, but I thought it was just luck. I've planted lots of daffodils because they are supposed to be poisonous to gophers. The little rodents seem to enjoy my lantana, though..

    • Hairdresser007 profile image

      James Jordan 8 years ago from Burbank, CA

      I love this lens. Great idea. I am trying to create a lens on irises but am waiting for my 1 iris to bloom. I want to create an iris area and there is an iris club not to far from here so hopefully I can get some good info. Thank you for this one!

    • profile image

      anonymous 8 years ago

      It wouldn't know a toxic flower, just haven't read up on that much at all. This is good information. I'd love to know more about mushrooms that we can eat from the wild. This is good information you have here and interesting. ~ Well done! - You are cool! :)


    • profile image

      bobtyndall 8 years ago

      Good information. Are you aware that rhubarb leaves are poisonous also. Although I have never heard of anyone getting sick from them. Also, these poisonous plants lose their toxicity in the compost pile.

    • Davidfstillwagon profile image

      Davidfstillwagon 8 years ago

      Good lens, the azealeas are about to bloom here in the South.


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      JewelRiver 8 years ago

      This is a great lens 5 stars!