Questioning Article's Accuracy: "7 Backyard Poisonous Plants That You Can Use As Medicine"

bcabrobin Posts: 251 ✭✭✭
edited October 2020 in Plant ID

*CAUTION: Reader, please be aware that this article was posted to question the validity of this article's advice. It has been discussed in great detail in following posts and the information within has been unanimously cautioned against. Please do not experiment/self medicate with poisonous plants as medicine as this is a dangerous practice. - Thank you, Admin*

Just read this and would like others thoughts.

Backyard Poisonous Plants That You Can Use As Medicine


Growing your own medicinal plants to concoct home-made remedies can be very satisfying, and it’s a tradition that still exists all over the world.

However, there are a handful of plants found in the backyard that if eaten, can cause serious harm, and potentially death. Some compounds in plants can also have a negative effect on prescribed medication, and there are numerous plants that should be avoided while pregnant. You do not want to be messing around with poisonous plants without some serious knowledge and a great deal of caution.

Despite the hazards, there are still a few poisonous plants that, when prepared correctly, can assist with certain conditions. Herbalists have a deep understanding of plants and their uses, and should be consulted to provide guidance and advice.

Formal studies are somewhat limited, and often, when a poisonous plant has been scientifically reported to alleviate, prevent or cure an ailment, it is usually an extraction of a few compounds. This is a highly refined laboratory process that eliminates the toxic elements. Obviously, this is not a process that can be replicated at home.

So, while it might not be recommended to pop out to the flower bed and pluck some foxglove to whip up your heart medication, there are a few poisonous plants that can be safely prepared at home.

#1. Flax

Common flax (Linum usitstissimum) was once a widespread crop that was harvested for its seed. Most people would be familiar with flax seed. It is a common food source all over the world, which makes it even more surprising to hear that it’s actually toxic.

Unripe seeds and plant materials have cyanogenic glycosides, which in a nutshell, turn into cyanide when crushed. Luckily, most of these compounds are actually found in the seed coating or husk, so once the seeds have been separated from the chaff, they are safer to eat in moderation.

And you should eat them! There are numerous benefits from eating flax seed. Research has shown that they are a good source of anti-oxidants, which therefore helps with inflammation. They’re also high in fiber so can help fight high cholesterol, obesity and colon cancer.

#2. Feverfew

Feverfew (Tanacetum parthenium) has the ability to lessen the intensity, frequency and duration of migraines. It’s reasonably well documented and there are studies to support this.

They look very similar to chamomile, but feverfew is not an herb you can lazily pluck and eat, so you certainly don’t want to get the two plants mixed up.

Chewing the fresh leaves of feverfew can cause swelling and blistering around the mouth, which is why it’s always advised to process feverfew before ingesting. There are three easy ways to do this:

  • Brewing it like a tea
  • Drying and grinding it up into a powder
  • Soaking it in alcohol to make a tincture.

If you’re allergic to plants in the daisy family, such as ragweed, marigolds or chrysanthemums, then this is definitely not the kind of plant you want to use to treat your migraines.

Related: 10 Teas That should Always be In Your Cupboard

#3. Comfrey

Comfrey (Symphytum officinale) contains alkaloids that might cause liver damage if eaten raw in large doses.

Most people either drink it as a weak tea, or topically (as a poultice or ointment) to treat bruising, inflammation, sprains, back aches and osteoarthritis, although small doses of the toxins can be absorbed through the skin, so it’s not recommended to use on a long-term basis, and don’t apply on broken skin.

Studies have found the potency of the plant depends on numerous factors, but some ways to reduce or eliminate the toxicity of comfrey include:

  • Harvest the leaves in the peak growing season during summer.
  • Pick older leaves instead of fresh new ones.
  • Dry out the leaves before drinking as a tea or eating.
  • Avoid using the root, which has the highest concentration of alkaloids.

For these reasons, it’s the perfect plant to grow yourself so that you have control over the quality.

#4. Aloe Vera

Aloe vera (Aloe barbadensis) is definitely a plant every garden should have, although the white latex layer between the skin and the gel is poisonous when eaten, and can irritate the skin in some cases. Once the latex has been washed off, then both the gel and skin can be eaten raw.

Its uses are well known and documented. It’s best applied topically for numerous skin conditions, and it’s usually just a matter of breaking a piece off the plant and applying it. This simple plant can provide so many types of relief:

  • Healing wounds quicker
  • Treating acne
  • Sun protection, as well as treatment for soothing sunburn
  • Anti-inflammatory, which makes it great for alleviating insect bites
  • Reducing itching in many skin conditions
  • Managing diabetes by decreasing blood sugar levels.

#5. Poppies

Poppies are another common poisonous plant you will find in many gardens. All 22 species of poppy have some degree of toxicity, but some of the milder varieties are still used as herbal remedies for helping with insomnia, stress and pain relief.

All parts of the plant are poisonous when still green and raw due to the white, milky sap present. Therefore, do NOT eat unprepared poppies. The toxicity is decreased by waiting for the poppy to completely dry out and turn brown, since it is less affected by the toxic sap at this stage. This is the best (and safest) time to harvest the seeds for replanting or eating.

The most popular poppy to use medicinally is the California poppy (Eschscholzia californica). However, this is definitely a plant that you have to grow yourself since it is illegal to harvest from the wild.

A single, fresh poppy plant (leaves, stem, flower and seed pod) can be used to make a tincture – simply chop up the plant, shove it into a jar, fill with alcohol and shake. Six weeks later you can strain it and use it.

Like all home-made products, you should always test it in low doses first (a few drops at a time), and use it sparingly.

#6. Rhubarb

Another common plant in the vegie patch that is poisonous is rhubarb. The leaves are very poisonous, but fortunately the stalks are fine to eat, even raw (if you don’t mind the tart flavor).

The leaves are toxic due to their high content of oxalic acid, which results in kidney problems and possibly death. Just 25 grams of oxalic acid is enough to be fatal. But on the other hand, the leaves have been reported to make a good insecticide, particularly against herbivores.

The multitude of health benefits that rhubarb (stems and roots) claims is backed by some sound research:

Cream containing rhubarb and sage was found to be as effective as over-the-counter creams for cold sores.

When used like a mouth wash, it sped up the time it took for canker sores to heal.

An extract of rhubarb was found to reduce the symptoms of menopause.

The list goes on!

#7. False Hellebore

False hellebore (Veratrum sp.) is last on the list because it’s probably the most hazardous.

One traditional way to minimize the risk of poisoning is to harvest the roots in fall, after the leaves have died back, and then dry them in order to make a weak tea for hypertension, decreasing your heart rate and lowering blood pressure.

For a long time, it was approved to treat these 3 conditions, but the toxicity of the plant has meant it has been superseded by a refined extract instead.

Therefore, this is a plant that you should be very wary of, and if you choose to use it, then it should be sparingly and in micro doses (0.02g – 0.1g). It has adverse interactions with a number of prescription medication, and numerous poisonings have been reported.

There are 10 species of false hellebore and some are classed as rare and endangered. The good news, is that you can buy the threatened California Hellebore from native nurseries and help perpetuate the specie.

Diligent research is a must if you want to use any of the poisonous plants listed above.


  • annbeck62
    annbeck62 Posts: 980 ✭✭✭✭

    Interesting information. Never thought of several of these as poisonous. I grew flax in the past but found it cumbersome to harvest and since it's inexpensive to buy stopped. I still grow my own aloe and use the flesh both internally and externally. Never knew the white layer was poisonous but maybe that's why I instinctively didn't throw the whole leaf into the blender.

  • Ferg
    Ferg Posts: 285 ✭✭✭

    @torey - I think in some parts of the country people grow flax for the flowers.

    Thank you for your comment. As I was reading the article, I was thinking that there are so many other things that could be used that are not tricky to work with (like hibiscus for migraines) that why give inexperienced people a chance to hurt themselves? I'm sure Datura has some benefits as well, but I'm not going there!

  • Torey
    Torey Posts: 5,396 admin

    @Ferg I was going under the assumption that if people were growing flax as a flower, they probably aren't getting enough to harvest for the seed. As @annbeck62 stated, it isn't easy to harvest and process and is so cheap to purchase, already to use. But it is a good caution for anyone growing flax in their flower gardens, who may have small children or pets that might eat it. I'm not sure what the toxicity threshold is but I think it would take eating more than just a few seeds from a garden plant to make one sick. And they aren't pleasant to eat with a husk. Perhaps someone else can answer the toxicity threshold question for us.

    Feverfew is quite bitter taken as a tea. I think most people who are using it to treat migraines are using it in a supplement form. There is a commercial product called MigreLief as well. So there is no chance of confusion with other species when using feverfew like that. As I said, it doesn't work for everyone but for some it is the only thing that does work. But good caution for those who are not experienced with plants.

    The thing I was most concerned about in this article was the suggested use of Veratrum species.

  • bcabrobin
    bcabrobin Posts: 251 ✭✭✭

    Thank you everyone for your thoughts I was hoping I wasn't the only one with those thoughts. Very miss leading on some of some of these.

  • Ethereal Earth
    Ethereal Earth Posts: 142 ✭✭✭

    I feel like the title is straight click bait. Using anything deemed poisonous from the backyard without training is almost guaranteed to cause problems. I can see where the thought of providing options to heal without the high cost of medicine or risk or going to a medical facility given the current pandemic, but the author should have focus on less common but still safe plants that grow. Or even unusual varieties or plants or common plants that can be used in unusual ways. As it is now there is some serious negligence going on.

  • judsoncarroll4
    judsoncarroll4 Posts: 5,282 admin

    @torey Ditto on hellebore... that is the main plant folks end up poisoning themselves with where I live. Oddly enough, "doll's eyes" Actaea pachypoda is also common.... sometimes mistaken for angelica... but just plain creepy looking to me!

  • judsoncarroll4
    judsoncarroll4 Posts: 5,282 admin

    Oh yeah... belladonna/jimson weed poisonings are seasonally prevalent.... folks smoking rhododendron, too... not good. Water hemlock poisonings are fairly rare. Mushroom poisonings are occasional.

  • Torey
    Torey Posts: 5,396 admin

    @judsoncarroll4 We have a different Actea species here. A. rubra. Baneberry is a common name for it here or Chinaberry, but also sometimes Doll's Eyes. It is very easily mistaken for Sweet Cicely (Osmorhiza species) when it has just come up. It can also resemble water hemlock, and other Apiaceae plants including Angelica, at some stages. A lovely plant but one to make absolutely positive identification on. So I don't harvest Sweet Cicely until there are identifiable flowers or fruits on the plants. That;s one I don't want to make a mistake with.

    There should be a caution on Apiaceae species for anyone wildcrafting. There are some like Sweet Cicely and Angelica that are delicious edibles and digestives, however, they can look very much like the very poisonous Water Hemlock (Cicuta douglasii) or Poison Hemlock (Conium maculatum). Cow Parsnip (Heracleum lanatum) is used at a very early stage for a brief period in the spring but at later stages can cause numbness and swelling of the throat, enough to impede breathing. However, the other Heracleum, H. mantegazzianum, is extremely toxic and can cause severe chemical burns with very long lasting effects. Both are very similar in appearance when young and could possibly be confused by a novice with Angelica or one of the above Hemlocks.

  • Desiree
    Desiree Posts: 255 ✭✭✭

    I have seen so many posts online in blogs, Facebook, Instagram, etc. on herbal (home) remedies lately that some of them almost terrify me. I am relatively new (about three years) to studying and learning herbalism. I started with free webinars being offered by experienced herbalists until I found one that resonated with me and enrolled in their school.

    In the early phase of my journey I was very cautious in my remedies, using only the things that were either already formulated and made or plants that I knew I couldn't mistake (plantain). I was surprised to learn that many people mistakenly identify dandelion for many lookalikes (common names: Cat's Ear, Hawkweed, Sow Thistle, Lesser Hawk Bit). While these may not kill you so many others can. I am have taken an in depth botany course so that when I see a plant I know exactly what it is and how to properly harvest, process and use it. If I am not 100% confident in my identification, I take pictures of as much identifying features, note in my journal where it is located, what is growing around it etc. and then I will research when I get home. If it's good, I know where to go back, if it's bad I know what to avoid in the future.

    A lot of herbalists have said that just because a plant may have certain properties/energetics/affinities (choose your word) doesn't necessarily make it the right plant to use. Sometimes there are simply less dangerous plants that will achieve a similar result without the potential dangers.

    I am so thankful to have found communities like HGN and others that provide the education and support that helps spread the natural way of life.

  • Linda Bittle
    Linda Bittle Posts: 1,469 ✭✭✭✭✭

    It makes me happy to see that we are in agreement about using herbs safely!

    Good grief, it's not like there are not hundreds of safe herbs for nearly any malady. We don't have to use risky ones, and if we decide to, it should only be under the supervision of a trained herbalist!

  • Annie Kate
    Annie Kate Posts: 680 ✭✭✭✭


    Thanks for the info about avoiding the latex in aloe vera; I was not aware of that. Not that I've ever used any from my houseplant, but I was always comforted by the fact it was there if needed. I've been reminded to be careful. By the way, our local grocery store sells huge aloe vera 'leaves' in the ethnic vegetable section.

  • karenjanicki
    karenjanicki Posts: 947 ✭✭✭✭
    edited October 2020

    Personally I'm not comfortable utilizing poisonous plants for medicine. I know they are sometimes used by very experienced herbalists but I would leave that up to them. I have only been studying herbalism for just under 2 years. I feel comfortable utilizing safe, familiar or well documented plants with a few solid herbal remedies, infusions and decoctions, salve, tinctures, poultices etc. But they each must be well known and understood. My concern is that since quarantine more people are starting to take an interest in herbalism but not really taking the time to properly identify or understand how to work with each individual plant. On other social media sites I have seen people asking for plant IDs. As soon as someone says "oh it such and such and it's edible", the op is ready to make up a salad. Often the people answering are wrong and even if they id it correctly, if the poster is without an understanding of the plant and it's benefits, contraindications and potential toxicity or toxic look alikes I fear this increase may lead to serious or even fatal consequences.

  • Torey
    Torey Posts: 5,396 admin

    One of the things that I think sets TGN apart is we have a great selection of practitioners and very knowledgeable gardeners/farmers here that can offer experienced perspectives on a wide variety of subjects in addition to herbal medicine. If someone has questions, they generally get very good answers. If there is a post made in error or out of inexperience, there are usually responses that will correct the info. Great blog articles and many good resources available through the Academy, too.

    This is a safe place to come for reliable information and a great learning platform for those who are new to any of these subjects that encourage us to have a more natural way of life.

    Thanks, TGN.

  • LaurieLovesLearning
    LaurieLovesLearning Posts: 7,210 admin

    When I first read this, I thought that it might be something that I would have to delete...or something. The title (and the source, as they have had accuracy issues in the past) made my red flag go up quickly. Of course, I read further.

    @bcabrobin Thank you for bringing this article to light & asking about it so that a proper assessment could be done. It is important to be wary of any herbal advice. Online articles & even some books can carry very dangerous suggestions & practices.

    I am so glad that the discussion has gone the way it did. Thank you all!

    *I am going to post a caution within the original post so that we don't have anyone jumping to conclusions about the article's advice, or jumping to any incorrect judgements of the forum because they didn't read very far...that we support exploration of poisonous plants & support/promote risky information.

    I will also try to alter the title slightly if I can to keep people from assuming things that they should not as well.*

  • AngelaOston
    AngelaOston Posts: 247 ✭✭✭

    Great information- thanks for raking the time to writing such a great guide!

  • LaurieLovesLearning
    LaurieLovesLearning Posts: 7,210 admin
    edited October 2020

    @AngelaOston I want to be sure that you understand that this post was posted to question the article's content. Please don't misunderstand my response here. It is very much out of respect for you & concern for safety.

    I am writing this out of caution & concern to remind you and others to be very careful with online medical information as some can be dangerous. Many knowledgable members here have expressed their concern with the article & its content. I & they would hate to have anyone harmed by following this dangerous advice.

    Only very experienced, qualified herbalists should be handling the more dangerous plants & herbs. Dabbling without a full knowledge can bring harm & even death.

    This is a reminder (to all) to be careful of sources of information and to be careful what one dabbles with.

    One great piece of advice I have heard is to check a minimum of three trusted sources before moving forward if something is new. I would caution about using sensational sites and would refer people to highly respected herbalists in lieu of these.

    Michael Moore, Rosemary Gladstar, Rosalee de la Forêt, Herb Mentor/Learning Herbs, K. P. Khalsa, & Susun Weed would be good examples. Their websites & books should be safe to scrutinize information by. I know that there are many more.