By: Nikki Tilley, Author of The Bulb-o-licious Garden
If you’ve read my book The Garden Crypt, then you know all about my fondness towards unusual things in the garden. Well, creating a poison garden is something that’s right up my alley. Before some of you get alarmed, let me make one thing clear – this type of garden is NOT to be used for malicious purposes and by all means, if you have pets or small children, DO NOT attempt to grow a toxic plant garden! With that said, those who are interested in this unique garden space, read on to learn more.
Creating a poison garden need not be so morbidly named or crafted. Make it your own, like you would for a recipe. Put your favorite “toxic” herbs in a corner of the landscape… fenced off from other more traditional plants. Showcase old-world specimens with a long history surrounded in lore. Choose commonly seen plants once found in a witch’s garden. Likewise, you might want to stick with everyday toxic garden plants. Yes, there are more than you might think. In fact, many commonly grown plants are actually poisonous in some fashion.
As with any garden design, there are certain to be various ways to create a toxic plant garden, and this is what makes gardening so fun. No one garden is exactly the same. Feel free to put your own spin on it, but just to keep things safe, it never hurts to heed a few helpful tips along the way. So as you’re creating a poison garden in your landscape, you may want to take these ideas into consideration:
Now that you have a few ideas to help get you started, it’s time to choose some plants for the poison garden theme. Since, in reality, it could be argued that most plants in some way or other have toxic properties, it would be impossible to name them all.
Even the plants we do have listed below are poisonous in varying levels and in different ways. Some may be toxic if you ingest the leaves, while others are toxic if you eat the roots. Some may simply make you very sick if you eat the poinsonous parts while others can cause death. None of the plants we have listed are deadly poisonous simply by touch, though a few can leave a nasty rash if you touch the leaves or sap with your bare skin. That being said, here are some toxic garden plants that will fit right in, some well-known and others with an interesting history:
Disclaimer: The contents of this article is for educational and gardening purposes only. Before adding any of these plants to a garden, research them carefully and ALWAYS handle toxic plants appropriately. NEVER plant these in areas frequented by animals or children.
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Poison ivy, poison oak, and poison sumac are a hazard year-round. Here are tips for preventing and treating the itchy rash and blisters.
First comes the itching, then a red rash, and then blisters. These symptoms of poison ivy, poison oak, and poison sumac can emerge any time from a few hours to several days after exposure to the plant oil found in the sap of these poisonous plants. The culprit: the urushiol oil. Here are some tips to avoid it.
Because pokeweed (Phytolacca americana) was featured in Tony Joe White's popular 1968 song, "Polk Salad Annie," some people have become aware that pokeweed (or simply "poke") has traditionally been eaten in parts of the southern United States. Despite the song title, the more proper way to spell the dish in question is "poke sallet." That's because it's not a salad but rather greens harvested from a young pokeweed plant and cooked as you would spinach.
However, fewer people realize that all parts of this potentially lethal plant are considered poisonous. Those in the South who have traditionally made poke sallet know exactly how to cook it to remove the toxins. If you don't possess such knowledge, you shouldn't be eating any "poke salad." And young children playing in the yard should definitely not be allowed to nibble at pokeweed.
The reason pokeweed plants so often crop up in people's yards is that wild birds eat the berries, then they deposit the seeds, which can sprout up at the edge of a garden or in some neglected area of the landscape.
If you're trying to get rid of pokeweed, be aware that it has a deep, long taproot. You must dig out this taproot entirely to eradicate the plant. Lest new plants should spring up from seed, remove and dispose of any berries produced.
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Poison-hemlock grows throughout the United States. It is very toxic and sheep, cattle, swine, horses, and other domestic animals are poisoned by eating small amounts of green or dried plant. It is also extremely poisonous to humans. Poison-hemlock is sometimes confused with western water hemlock, a more deadly species, because the names are similar. Poison-hemlock is commonly called deadly hemlock, poison parsley, spotted hemlock, European hemlock, and California or Nebraska fern.
Poison-hemlock has white flowers that grow in small erect clusters. Each flower develops into a green, deeply ridged fruit that contains several seed. After maturity, the fruit turns grayish brown. Poison-hemlock starts growing in the early spring. It usually grows for 2 years, but in favorable locations it may be a perennial. Roots of poison-hemlock may easily be mistaken for wild parsnips. Poison-hemlock grows along fence lines, in irrigation ditches, and in other moist, waste places. It may be 2 to 3 meters tall. The hollow stem usually is marked with small purple spots. Leaves are delicate, like parsley, and it has a white taproot. Poison-hemlock is a biennial in the parsnip or wild carrot family.
All parts of poison-hemlock (leaves, stem, fruit, and root) are poisonous. Leaves are especially poisonous in the spring, up to the time the plant flowers. Fresh leaves are unpalatable, so livestock seldom eat hemlock when other feed is available. The toxic compounds are coniine, g-coniceine, and related piperidine alkaloids. People may be poisoned by eating any part of a hemlock plant. Often, poisoning occurs after the victim confuses hemlock root with wild parsnips, hemlock leaves with parsley, or hemlock seed with anise. Whistles made from hollow
stems of poison-hemlock have caused death in children.
Where and When It Grows
Because of its attractive flowers, poison-hemlock was brought to the United States from Europe as a garden plant. It is moving onto rangelands. Poison-hemlock is found at roadsides, on edges of cultivated fields, along creekbeds and irrigation ditches, and in waste areas.
How It Affects Livestock
Poison-hemlock ingestion frequently is fatal. Sheep may be poisoned by eating as little as 100 to 500 gm of green leaves. Cattle that eat 300 to 500 gm may be poisoned. Signs usually appear within an hour after an animal eats the plant. Animals die from respiratory paralysis in 2 to 3 hours. Convulsions, which are common in western water hemlock poisoning, seldom occur with poison-hemlock.
Skeletal deformities or cleft palate may be induced in offspring of cows, sheep, goats, and pigs that eat poison-hemlock during gestation. Susceptible stages of gestation when animals should not be exposed to this plant include 40 to 70 days in cows and 30 to 60 days in sheep, goats, and pigs. Palate and skeletal deformities in calves are indistinguishable from the lupine-induced crooked calf disease.
Signs and Lesions of Poisoning
How to Reduce Losses
Avoid stressing animals that are not recumbent. For recumbent animals, support respiration and treat with activated charcoal and a saline cathartic. Gastric lavage may be beneficial with atropine therapy to control parasympathetic signs. Animals that recover seldom show aftereffects, although pregnant animals may give birth to deformed offspring.
Poison-hemlock may be controlled by treating plants before they begin to bud with 2,4-D plus dicamba (1 kg + 0.5 kg ai/Ac). Repeat applications may be needed. Follow all precautions for handling herbicides.
The only living creature that can survive consuming even a small amount of hemlock is a goat… maybe. This deadly toxic weed looks incredibly like both Queen Anne’s Lace (wild carrot) and wild yarrow.
Typically, poison hemlock will not be found growing in an open field area in full sun like either of the two other common weeds that are highly prized for their medicinal properties by herbalists, but such cross growing patterns can happen.
Poison hemlock tends to thrive in partial shade in moist soil – like along the banks of a creek or river. After a particularly wet period, especially in the early spring, poison Hemlock is most likely to sprout.
Hemlock contains no fewer than eight powerful toxic alkaloid compounds including gamma-coniceine and coniine.
There is no treatment or antidote, for the consumption of poison hemlock. Hemlock poisoning symptoms typically materialize just 20 minutes after ingesting or inhaling spores.
Death typically occurs within three hours after not just consuming poison hemlock but inhaling spores into your nose or getting them into your eyes.
Poisoning via the eyes occurs from either rubbing them after touching the plant or from spores blowing in the wind. Death after the inhalation of hemlock tends to occur more rapidly than ingestion.
The toxins in hemlock cause the respiratory system to become paralyzed – or fail. It takes only a very small amount of toxic spores from a hemlock plant to kill. Consuming less than a walnut sized amount of hemlock will kill a cow.
Poison Hemlock Symptoms
The toxins in poison hemlock are usually released more easily when the plant is growing in a sunny area than when it is located in its more shady environment in moist but not semi-dry soil.
How To Identify Poison Hemlock
by Unbelievable Facts Dec 8, 2019, 9:00 am Comments Off on England’s Poison Garden, the Deadliest Garden in the World, Contains Around 100 Species of Poisonous and Intoxicating Plants
When you imagine strolling through an English garden, you may picture greenery all around, birds chirping, bees buzzing, and the sweet smell of roses wafting through the air. Well, you would have to adjust your expectations if you ever plan to visit the Poison Garden at the Alnwick Garden. As the name suggests, the Poison Garden is less than idyllic. It houses around 100 species of toxic plants, most of which are deadly. Though touching, smelling, or tasting these plants are strictly prohibited, some visitors have passed out simply from inhaling the fumes.
Situated right next to the Alnwick Castle in Northumberland, England, the Alnwick Garden was originally established by Hugh Percy, the 1st Duke of Northumberland, in 1750. By the end of the 19th century, thanks to the efforts of the 4th Duke, the garden was at its grandest with acres of flowers, avenues of limes, and yew topiary. However, during World War II’s “Dig for Victory” campaign, Alnwick Garden was used for growing crops and providing food. In the 20th century, due to post-war austerity, the garden fell into disrepair and was closed down in 1950.
The revival of the Alnwick Garden began in 1997 at the hands of Jane Percy, the 12th Duchess of Northumberland. With the help of world-renowned landscape architects Jacques and Peter Wirtz, Lady Percy returned the garden to its former glory. Today, it is an astounding complex of contemporary gardens featuring a water cascade, a maze of bamboo tunnels, a cherry orchard, a bar, a restaurant, and one of the biggest treehouses in the world! With a £42 million total development cost, the Alnwick Garden became the most ambitious garden built in the UK since World War II.
Image credits: Ian Capper /Geograph.org.uk
Inspired by the Orto Botanico di Padova in Italy, Lady Percy decided to add a section to the garden complex that would be dedicated entirely to toxic plants. The Poison Garden was added in 2005. Though it is just a part of the Alnwick Garden, it is certainly one of the most popular corners of the complex. Lady Percy believes that learning about the healing properties of plants is not enough. People, especially children, need to learn about how plants can also kill. Familiarizing and educating oneself with lethal plants, many of which often grow naturally in our backyards, is not just crucial but interesting as well.
The Poison Garden currently holds an extensive collection of deadly plants, many of which have been imported from different corners of the world. The most notable species on the list include Strychnos nux-vomica (commonly known as the “strychnine tree,” the source of strychnine), Ricinus communis (the source of castor oil and also the deadly poison called “ricin”), hemlock (which contains toxic alkaloids and is fatal even in small doses), Laburnum (also known as the “golden chain tree”), South American Brugmansia (an amazing aphrodisiac that can also kill), Atropa belladonna (commonly known as “belladonna” or “deadly nightshade”), Foxglove (a beautiful but deadly plant), and many others.
Image credits: Amanda Slater/Flickr
Upon reaching the entrance of the Poison Garden, you will be greeted by a pair of big black gates with a sign that says “These Plants Can Kill.” Though a fair warning, these words along with the skull and crossbones are not enough to deter visitors from entering. However, you are not allowed to go in without a guide, and there is 24-hour security to ensure that. Inside, you will find detailed information about each plant and its toxicity. Some of the plants are also kept inside cages. You are not allowed to touch, smell, or taste any of the plants. Doing so, as the sign reads, might kill you. In fact, in 2014, seven visitors passed out simply from inhaling the toxic fumes.
One of the most popular attractions in Northumberland, Alnwick Garden receives about 800,000 visitors per year.
Behind the 900-year-old stone walls of Alnwick Castle, the sinister side of botany blooms. Join us, if you dare, as we discover plants that have the power to poison, blind and kill.
Bone-chilling botany takes center stage in the Poison Garden at Alnwick Castle in Northumberland, U.K. This morbid garden features potent plants that earn a turn in the spotlight for one reason only: being lethal to humans. What’s most surprising about these plants is how common they are. You may even have a few growing innocently in your garden. Take a virtual tour of the Alnwick Poison Garden — if you dare!
Guarded by stone-carved lions, Alnwick Castle in the Northumberland region dates back to the 11th century. Look familiar? You may know it as Brancaster Castle in Downton Abbey or Hogwarts School of Witchcraft and Wizardry in the Harry Potter movies.
The Alnwick Poison Garden with its foreboding flora is part of 14 acres of gardens that have earned Alnwick Castle Gardens the nickname “Versailles of the North.” Poison Garden guided tours are free after you pay the entry fee to the castle gardens. Tours operate every half hour until 5 p.m.
Inside the Poison Garden, more than 100 dangerous plants grow under lock and key. Some are so hazardous they’re cultivated inside cages. This is definitely one garden where you don’t want to stop and smell the flowers. The Duchess of Northumberland created this morbid collection to help educate schoolchildren about the dangers of harmful and illicit drugs — the kinds of compounds these plants produce. Visitors to the garden are warned not to touch, smell or even stand near the plants.
Pale yellow flowers with black-veined petals and a dark center have earned black henbane (Hyoscyamus niger) a common name of devil’s eyes. Leaves of this herb emit a noxious odor that can be overwhelming, especially on a warm day in the walled Poison Garden. Visitors frequently collapse or even faint when they come near this plant, which is why there’s a bench nearby — and first aiders on standby. Because henbane was an important tool in herbal medicine of the ancient world, settlers carried seeds to the New World. Today the plant has spread throughout the Northeast, Midwest and West. All parts of this plant are poisonous to people and livestock.
In terms of perilous plants, giant hogweed (Heracleum mantegazzianum) is a definite contender for a top spot. With flowers that resemble dainty queen anne’s lace and a size that rivals Jack’s beanstalk, giant hogweed is tough to miss. Plants tower 8 to 14 feet high, an impressive size that’s tempting to pose beneath. But don’t be so fast to sidle up to this giant menace. Its sticky sap has the power to burn your skin, causing blisters (of the third-degree burn kind) that continue to appear for up to seven years. Breaking a mirror has nothing on this poisonous plant! If the sap gets in your eyes, blindness can result. Giant hogweed is reported heavily in the Northeast, Midwest and Pacific Northwest and is slowly spreading across the United States.
Perfumed blooms disguise the perilous nature of this exotic beauty. Angel’s trumpet, also known as Brugmansia, is a commonly sold container plant that’s often grown as an annual in cold winter regions. In warmest zones, gardeners typically cultivate it in tree form, allowing the long, trumpet-like blossoms to dangle. Angel’s trumpet is a potent hallucinogenic similar to LSD. Victorian ladies would keep a plant in the home and knock a few pollen grains into a teapot, turning the warm brew into a day-tripping sip for genteel lady visitors. All parts of the plant are toxic.
Alnwick Poison Garden includes a hedging plant that’s popular on both sides of the Atlantic: cherry laurel (Prunus laurocerasus). This fragrant evergreen produces cyanide from broken leaves or stems. During the Victorian era, laurel leaves played a key role in butterfly collections. Pop a butterfly into a jar, drop in a cut cherry laurel leaf, twist the lid on tight, and voila! — a (cyanide-poisoned) butterfly perfect for mounting. Avid British gardeners occasionally complain of headaches and dizziniess due to cyanide poisoning when hauling laurel hedge prunings to the yard waste drop. This event typically occurs on a warm day after clippings have sat in the car with the windows up, allowing cyanide to accumulate. A commonly planted U.S. variety is ‘Otto Luyken.’
A cottage garden classic, delphinium brings spires of beautiful blue blossoms to spring garden scenes. Lurking beneath the surface of this bloomer, however, are compounds that kill. The youngest parts of the plants deliver the most potent poison. In the West, wild delphinium (often called larkspur) kills livestock each year — animals die within a few hours of eating the plant. All parts of delphinium are poisonous, causing symptoms of abdominal pain and paralysis that leads to death. Wear gloves when deadheading, and make sure children or pets do not consume seeds.
Towering and sculptural, castor bean (Ricinus communis) commands attention in the garden with its deep red, star-like leaves. This tropical beauty hails from East Africa, but has naturalized in warmer regions of North America. In the garden, a plant easily tops 5 feet (or more) in a typical summer growing season. Gardeners love castor bean for its architectural appearance, including chunky seed pods. Seeds contain ricin, one of most deadly natural poisons — 6,000 times more poisonous than cyanide. Four seeds are enough to kill an average-size person. This is the poison used in the infamous umbrella gun in 1978 to take out Bulgarian dissident Georgi Markov on the Waterloo Bridge in London.
Common rue or herb-of-grace delivers its poison via phytotoxicity — like giant hogweed, it burns skin. Long revered for medicinal and culinary uses, rue (Ruta graveolens) became an herb garden favorite for its pretty appearance: dainty texture and blue-green leaves topped with yellow blooms. These days, it’s fallen out of favor due to its skin-burning properties. At Alnwick Poison Garden, a senior gardener spotted a weed growing up out of a clump of rue. Without thinking (or gloving up), the gardener pulled the weed and got rue sap on her hands. Within an hour, blisters formed on her hands that progressed to third-degree burns. This reaction is caused because the sap removes skin’s natural protection against ultraviolet rays. Once the sap is in your system, it lingers up to seven years.
Beloved for its blossom-packed spires, foxglove (Digitalis purpurea) brings cheerful color to the late spring and early summer garden. Blooms open in a literal rainbow of shades, including yellow, pink, chartreuse and purple. All parts of the plant are poisonous. Digitalis, a heart medicine, is produced from this plant. Often people make tea from the leaves, suck on flowers or nibble seeds. Doing these things is basically taking an unregulated dose of heart medicine, which can affect heart rate (slowing it down or making it irregular). This is a dangerous plant with lethal possibilities.
Pasque flower (Pulsatilla vulgaris) steals the spotlight in spring with blooms that open in shades including purple, white, wine-red and yellow. Ferny leaves form an eye-catching tuft. Blossoms, leaves and stems are covered in silvery hairs that add a textural element to the pretty plant. It thrives in dry soil and readily spreads to form a colony if you let it set seed. All parts of the pasque flower plant contain poisonous sap that produces skin irritation and violent convulsions.
Native to the United Kingdom and naturalized throughout the United States, Atropa belladdonna brings the poison power. Also known as deadly nightshade, this botanic assassin opens purple blossoms that fade to form sweet blue-black berries. Four berries can kill a child. During the Italian Renaissance in Venice, ladies of the court would drop juice from the berries into their eyes, which caused pupils to dilate and cheeks to flush — cosmetic tricks to enhance beauty (and eventually lead to blindness and death).
Spring’s sunny flower, the daffodil, is another member of the poison plant club. Every part of the plant is poisonous, from bloom, to stem, to bulb, where the toxin is most concentrated. You have to eat the plant to encounter the worst of its symptoms, including abdominal pain, vomiting, diarrhea and burning of the mouth, lips and tongue. These symptoms typically pass and aren’t usually fatal (the greatest risk is to children who eat bulbs). Cutting buckets of daffodil flowers leads to what’s known in the bulb trade as “daffodil picker’s rash,” a contact dermatitis caused by the pretty bulb’s sap. Gathering a few stems from your garden won’t give you a rash unless you have extremely sensitive skin.
Known as the crown imperial, Fritillaria imperialis is an impressive spring bloomer. Tall 3- to 4-foot stems topped with bell-like blossoms command attention. Bulbs boast a skunky scent that repels people and pests alike. It’s a good bulb to plant with tulips to discourage underground critters from feasting on tulip bulbs. A fritillaria bulb contains alkaloids called “imperialin” that are poisonous to people and animals. Eating a large quantity of bulbs is what delivers the fatal blow.
Also known as thorn-apple (due to its spiky seedpods), Datura is a night-flowering plant with richly perfumed blooms. Flowers are trumpet-shaped, slowly unfurling at dusk and lingering until about noon the following day. When jostled or crushed, leaves release a strong, offensive odor similar to rancid peanut butter. Plants grow quickly and readily self-sow — to the point of becoming invasive. Seeds and flowers are toxic, narcotic and hallucinogenic. Serious illness or death can result from ingesting the plant. Many municipalities forbid growing this potent plant.
For late-season color, it’s tough to beat Aconitum napellus. Also known as monkshood or wolf’s-bane, this pretty perennial opens purple flowers that last through light frosts. All parts of monkshood are poisonous if consumed, especially the roots, which contain aconitine, a heart and nerve poison. Historically, people used aconitum to poison spear and arrow tips for hunting and battle. The poison was a favored execution tool in ancient Rome. The name wolf’s-bane refers to the plant’s ability to repel wolves, both real and werewolves. In 2009, England’s infamous “Curry Killer” used a type of aconitum to kill a former lover. In the garden, wear gloves when handling aconitum to avoid a rash, especially if you have sensitive skin.
Early season blooms are the hallmark of Lenten rose (Helleborus) , which is sometimes called hellebore or Christmas rose. Leathery evergreen leaves and nodding blooms shine during winter months, with flowers appearing from late winter to early spring. Blossoms unfurl in many hues, including white, pink, burgundy and near-black (like the Dark and Handsome variety seen here). All parts of the plant are poisonous, although roots contain the highest concentrations of harmful compounds, which induce vomiting and can lead to death.
As the name suggests, flowering tobacco (Nicotiana sylvestris) is one of the plants used to develop the tobacco plant. It’s a warm-weather plant that grows 3 to 5 feet tall. Flowering tobacco opens perfumed white blooms that cascade like exploding fireworks. The flowering tobacco family includes over 60 species, all of which are toxic if ingested because they contain nicotine, which affects nerves controlling heart rhythm. Keep plants away from pets, livestock or curious children who might be tempted to nibble leaves.
Beautiful but deadly, oleander is a beloved hedging plant in warm-weather regions and a pretty houseplant in colder zones. Large flower clusters open non-stop from early summer to mid-autumn in many shades, including pink, red, yellow and white. This dense evergreen shrub is intensely poisonous. A single leaf can kill a child, and even honey made from the blooms delivers a non-lethal dose of poison. Red-flowered varieties contain the highest levels of toxic compounds.
A welcome harbinger of spring, snowdrops (Galanthus) open dainty blooms in early spring, often while snow flurries still dance in the air. These spring flowers contain a nasty compound in their bulbs that, when eaten, leads to dizziness, nausea, diarrhea and, in extreme cases, death. In early spring, people often mistake the strappy leaves of snowdrops for spring onions, pull them up and munch the bulbs. Eating more than three bulbs produces symptoms, but you have to eat a pile of them to induce death.
With its pumpkin-orange seedpods, Chinese lantern (Physalis alkekengi) is the perfect autumn plant. It grows easily, thriving in a sunny spot. Plants are hardy to Zone 6, but readily self-sow, spreading to fill in garden beds (to the point of being invasive, so choose your planting spot with care). Chinese lantern is related to Atropa bella-donna and, like that plant, contains atropine compounds in leaves and seeds. The poison affects people, as well as livestock, and can cause death when eaten.
Japanese pieris (Pieris japonica) earns a place in the landscape for its evergreen nature and late winter-early spring flowers. Also known as lily-of-the-valley shrub, this pretty bloomer packs a deadly punch. All parts of the plant are toxic, containing over 30 different chemicals that affect the heart. Even honey made from the flowers of this shrub is poisonous. The toxins in pieris affect livestock, pets and people. For cattle and goats, the toxic dose is 0.2 percent of the animal’s body weight.