10 Houseplants You Might Not Know Are Poisonous - Backyard Boss
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10 Houseplants You Might Not Know Are Poisonous

Houseplants are a great way to bring nature indoors, especially if you live in an apartment or home without backyard space. Some make cheery additions to low-light spaces, while others boast air purifying or medicinal properties. Unfortunately, some of these plant beauties can be toxic to humans and animals. It is important to research every plant you are looking to bring into your home, as toxicity information is not commonly found on new plant tags. Anyone living with small children or pets should be especially aware, as curiosity may lead to accidental poisoning.

Poisoning can happen from ingesting a plant; either its leaves, berries, blossoms, or roots. Skin contact with leaves, sap, or juices from the plant can also be unhealthy if the plant is toxic. Be aware of how available a plant’s soil and water tray are. These may entice curious children or pets to ingest their contents.

Luckily, many of these toxic plants require a person or pet to ingest a lot before they experience poisoning symptoms. You can look for alternatives to these plants if you are highly concerned and want to avoid any chance of accidental poisoning. Otherwise, you may just need to relocate your toxic plants out of reach of small children and curious pets.

1. Arrowhead

Arrowhead Leaves
Image Credits: ilham_abitama17 via Pixabay

The first toxic plant on our list is the arrowhead plant. Arrowheads begin as bushy plants with heart-shaped foliage. Once the plant has matured it will grow climbing stems and the arrow-shaped leaves it is named for. Arrowheads make common gifts and can be found among the mix in a dish garden.

Arrowheads are mildly toxic to both humans and animals. Common poisoning symptoms include irritated skin, upset stomach, and vomiting.

While arrowheads may simply be relocated, you do still need to mind their leaves. They constantly shed, so keeping fallen leaves out of reach is important!

2. Dieffenbachia

Dieffenbachia Leaves
Image Credits: Alexey Demidov via Pexels

The dieffenbachia, or dumb cane, is the second toxic plant on our list. They grow up to 5 feet tall in low-light conditions, making great additions to your indoor garden. Their thick cane stems and large fleshy leaves create a tropical vibe in spaces where it may be hard to grow other plants. However, dieffenbachia is moderately toxic to both humans and animals. As they are usually kept in pots on the floor, they pose a risk to those within reach.

When ingested, dieffenbachia produces a range of poisoning symptoms. These include extreme pain or burning in the mouth, salivation, swelling and numbing of the throat, nausea, vomiting, and diarrhea. The sap of a dieffenbachia may cause a rash or itchy skin. When ingested the sap causes the tongue to burn and swell, blocking air from the throat. Ingestion may also cause tears in the soft tissue of the throat, resulting in inflammation or swelling and the inability to speak. Contact with eyes can cause painful cornea damage.

For these reasons, it is best to use gloves when handling a dieffenbachia. You may want to consider an alternative to this one if you have toddlers or pets roaming around your floor.

3. Snake Plant

Snake Plant in Lit Room
Image Credits: Rosana Solis via Pexels

Mother-in-law’s tongue, commonly referred to as the snake plant, is third on our list. This exotic beauty is a favorite houseplant for its air purification properties and striking appearance. Snake plants have a sleek, upright shape with hard, leathery leaves that grow up to a point. They are generally variegated green in color with strips of yellow or white.

Unfortunately, snake plants are usually grown in floor pots putting them within reach of children and pets. All parts of this plant are poisonous and produce short-lasting symptoms when ingested by humans. These include mouth pain, salivation, and nausea. Snake plants pose more of a risk to cats and dogs who may also experience pain, vomiting, and diarrhea with ingestion.

4. Philodendron

Green Philodendron Leaves
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Perhaps one of the most common houseplants, philodendrons are loved for their growing ease and aesthetic appeal. They are non-vining or vining, reaching lengths up to 8 feet.

Ingested philodendrons produce mild side effects in humans. These include dermatitis reactions, burning of the lips, tongue, and throat, swelling of the mouth and digestive tract, vomiting, and diarrhea. You really want to keep these away from curious children, as ingesting large amounts may be fatal.

Philodendrons appear to be more toxic to cats than dogs, though both may experience symptoms if ingested. Watch for spasms, seizures, pain, and swelling to determine whether your pet has been poisoned.

It is best to keep this toxic beauty up high, where its long vines and leaves will not be accidentally ingested!

5. English Ivy

Variegated English Ivy in White Hanging Pot
Image Credits: Kulbir via Pexels

English Ivy is a beautiful climbing and trailing vine plant. It creeps over brick walls and cascades elegantly from hanging baskets. English ivy produces solid green or variegated leaves. Their vines have the ability to grow up to 6 feet indoors.

Unfortunately, these too are toxic when ingested in large quantities. Humans may experience skin irritations such as rashes with contact. Ingestion causes burning in the mouth and throat making it difficult to breathe. In extreme cases, the symptoms may include fever, vomiting, stupor, convulsions, delirium, and hallucinations.

Be aware of the risks english ivy poses, and keep this beautiful vine up high and inaccessible!

6. Pothos

Green Potted Pothos Plant
Image Credits: sweetlouise via Pixabay

Pothos are adored for their forgiving nature and growing ease. With little care, this evergreen vine can grow up to 8 feet indoors. They also require low light and are very suitable for apartments and dark rooms. The pothos leaves come in solid or variegated greens that boast air purification properties.

Unfortunately, the calcium oxalate crystals found in these plants can be toxic to both humans and pets. If ingested humans may experience burning mouth, lips, and tongue, swelling of the throat, skin irritations, vomiting or diarrhea. Cats or dogs who take an interest in your pothos may begin drooling or choking as their mouths and tongues swell. This can also cause breathing difficulty and stomach issues. In extreme cases, pothos poisoning can lead to renal failure and even death.

Keep pothos up high on shelves or hanging baskets away from curious children and hungry pets!

7. Peace Lily

Peace Lilies
Image Credits: HOerwin56 via Pixabay

Peace lilies, though not true lilies, are beautiful evergreen perennials that make common indoor houseplants. Their green foliage deepens in color as the plant ages, boasting shiny leaves with visible veins. The peace lily is aptly named due to its perky white flowers that resemble a waving peace flag.

This beauty contains the same calcium oxalate crystals as the pothos which pose a poisoning risk when ingested in large quantities. In humans, the symptoms include: burning or swelling of the lips, mouth, and tongue, difficulty speaking or swallowing, vomiting, nausea and diarrhea. Poisoned pets also show signs of excessive salivation, dehydration, and a lack of appetite. If left untreated, extreme cases of pet poisoning may lead to renal failure.

While peace lilies pose potential risks, they are great air purifiers who thrive in apartments and low-light rooms. Ensure your plant is out of reach for continued peace lily enjoyment!

8. Caladium

Green and Red Caladium Leaves
Image Credits: mschiffm via Pixabay

Caladiums, like the peace lily, are common household plants as they have the ability to grow in low-light conditions. They have long-lasting, arrow-shaped foliage in a multitude of variegated colors. These include: red, pink, white, and yellow.

Unfortunately, all parts of the caladium plant are toxic, posing a risk to both humans and animals. Painful burning and swelling of the mouth, tongue, lips, and throat may cause breathing, speaking, and swallowing issues in poisoned humans. In extreme cases, a blocked airway can be fatal. Cats and dogs may experience nausea, vomiting, staggering, head shaking, drooling, and difficulty breathing.

Keep your children and pets safe by finding a safe, unreachable home for your caladium.

9. Sago Palm

Sago Palm Near Fence
Image Credits: Olena758 via Pixabay

The sago palm is an ancient plant that can contribute its success to its poisonous properties. Most animals do not eat sago palms, and for good reason!

These tropical mini-palms grow slowly to a height of 5 feet tall indoors. All parts of the plant are toxic, though its seeds are most toxic to pets. Cats and dogs may experience severe gastrointestinal and nervous system issues. Poisoning by a sago palm may also cause liver damage in your beloved pets.

While the tough fronds may not be appealing to your pets to gnaw on, keeping a sago palm away from persistent critters is a good idea due to their toxic nature.

10. Oleander

Pink Oleander Shrub
Image Credits: Hans via Pixabay

Oleander, though not often grown indoors, makes an appearance on our list due to its extreme toxicity. All parts of the oleander plant are extremely toxic to both humans and animals. One leaf can be fatal, so it is important to be aware of the risks this plant poses in your home or garden.

Oleander, like the sago palm, is an ancient plant. This flowering shrub produces large clusters of red, pink, yellow, or white, single or double blossoms from early summer until mid-fall. Their leathery leaves are long and narrow and come to a pointed tip.

Poisoning symptoms in humans include arrhythmia, dizziness, tremors, as well as gastrointestinal, vision, skin, circulation, and nervous system issues. Pets may experience arrhythmia, vomiting, and cold extremities.

Use extreme caution if you find or plan to add oleander to your garden. Keep this guy well out of reach of your children and pets!

What We’ve Learned

Houseplants are a great way to bring nature inside your home. They add charm to any indoor space. Those that require little light make great additions in apartments and dark rooms. Some help with air purification while others may be edible or used medicinally. However, always do your research before leaving your houseplants in reach of small children and pets. Toxicity information may not be provided on new plant tags, and some poisonous plants may surprise you!