Toxic plants

Atropa belladonna

Toxic parts: Berries, leaves and roots

Tropane alkaloids cause blurred vision, racing heartbeat, hallucinations, seizures and death.

Conium maculatum

Toxic parts: All parts, especially the seeds

Coniine causes progressive paralysis — it shuts down the muscles that keep you breathing. Often mistaken for wild carrot or parsley.

Cicuta maculata

Toxic parts: All parts, above all the roots

Cicutoxin triggers violent, uncontrollable seizures that can kill within hours. Widely called North America's most poisonous plant.

Nerium oleander

Toxic parts: Every part, including smoke from burning it and water in its vase

Cardiac glycosides disrupt the heart's rhythm; a few leaves have been fatal.

Digitalis purpurea

Toxic parts: All parts, including the flowers and seeds

Digoxin-like compounds can stop the heart. Confused with comfrey or borage by foragers, with deadly results.

Convallaria majalis

Toxic parts: All parts, including the water cut stems stood in

Cardiac glycosides cause dangerous heart arrhythmia — just a few berries or leaves can poison a child.

Ricinus communis

Toxic parts: Chewed seeds (whole swallowed seeds usually pass through)

Ricin is one of the most potent plant toxins known; chewing a handful of seeds can be fatal days later.

Abrus precatorius

Toxic parts: Chewed seeds — intact seeds are used as beads

Abrin is even more toxic than ricin by weight; a single chewed seed can kill an adult.

Aconitum napellus

Toxic parts: All parts, especially the tuberous roots

Aconitine numbs the mouth, then causes deadly heart arrhythmia — it can even poison through unbroken skin. Wear gloves.

Brugmansia spp.

Toxic parts: All parts, especially flowers and seeds

Tropane alkaloids cause delirium, overheating and seizures; poisonings from ornamental gardens are not rare.

Taxus baccata

Toxic parts: Needles and the seed inside the red berry (the red flesh itself is not toxic)

Taxine alkaloids cause sudden heart failure, sometimes with little warning.

Hippomane mancinella

Toxic parts: Fruit, sap, bark and even smoke from its burning wood

The 'little apple of death' causes severe internal burns; rain dripping off the tree blisters skin. Found on Caribbean and Florida coasts.

Dieffenbachia seguine

Toxic parts: Stems and leaves

Calcium oxalate crystals cause burning, swelling and drooling; severe swelling can block the airway.

Narcissus spp.

Toxic parts: Bulbs above all; leaves and flowers also

Vomiting, diarrhea and trembling; large amounts of bulb can affect the heart. Florists get skin sores from the sap.

Tulipa spp.

Toxic parts: Bulbs above all; leaves and flowers also

Tulipalin irritates the mouth and stomach and causes vomiting; handling bulbs can trigger contact dermatitis.

Rhododendron spp.

Toxic parts: Leaves, flowers and nectar (incl. 'mad honey' from rhododendron nectar)

Grayanotoxins cause burning, vomiting, low blood pressure and irregular heartbeat.

Hedera helix

Toxic parts: Berries and leaves

Saponins burn the mouth and cause vomiting and diarrhea; sap also irritates skin.

Spathiphyllum spp.

Toxic parts: All parts

Calcium oxalate crystals cause painful burning and swelling of the mouth and throat.

Epipremnum aureum

Toxic parts: Leaves and stems

Calcium oxalate crystals cause burning, mouth swelling and vomiting.

Hydrangea macrophylla

Toxic parts: Buds, leaves and flowers

Cyanogenic glycosides can release cyanide in the gut, causing dizziness, vomiting and shortness of breath.

Wisteria spp.

Toxic parts: Seed pods and seeds; bark to a lesser degree

Lectins cause severe vomiting, diarrhea and dehydration — sometimes days after eating just a few seeds.

Sambucus spp.

Toxic parts: Unripe berries, leaves, stems, bark and roots

Cyanogenic glycosides cause nausea and vomiting; only fully ripe, cooked berries are safe to eat.

Rheum rhabarbarum

Toxic parts: Leaves (the stalks are safe)

Oxalic acid causes vomiting, kidney stones and, in large amounts, kidney damage.

Solanum tuberosum

Toxic parts: Green or sprouted tubers, sprouts, leaves and stems

Solanine causes vomiting, diarrhea, headache and, in serious cases, confusion and weakness.

Solanum lycopersicum

Toxic parts: Leaves, stems and unripe green fruit

Tomatine and solanine cause vomiting and dizziness; ripe fruit is perfectly safe.

Ipomoea tricolor

Toxic parts: Seeds

Lysergic acid amides cause hallucinations, nausea and diarrhea — poisonings usually come from deliberately eaten seeds.

Euphorbia pulcherrima

Toxic parts: Milky sap in leaves and stems

Irritates the mouth and stomach and can inflame skin; its deadly reputation is a myth.

Chrysanthemum spp.

Toxic parts: Flower heads and leaves

Pyrethrins cause stomach upset and contact dermatitis in sensitive people.

Kalanchoe blossfeldiana

Toxic parts: All parts

Usually vomiting and diarrhea; very large amounts can affect the heart.

Euphorbia spp.

Toxic parts: Milky white sap

Burns and blisters the mouth, skin and eyes on contact.

Aloe barbadensis

Toxic parts: The yellow latex layer under the skin (gel is safe)

Anthraquinones cause painful cramps and diarrhea; the latex is a laxative drug, not a food.

Malus domestica

Toxic parts: Seeds only (swallowed whole they pass harmlessly)

Crushed or chewed seeds release amygdalin, which forms cyanide — small amounts cause dizziness; a large chewed quantity is dangerous.