This is not an exclusive list so always take care.

Hazardous and Dangerous Plants

Not everything in the garden is lovely when it can poison or injure the unsuspecting. The extremely hazardous Poison Ivy and Poison oak related to the Rhus family (Diversiloba, radicans, vernix, succedanea, toxicarium and veniciflua) should be avoided at all cost. Other highly harmful plants are listed below and the effects of eating roots berries or leaves can be serious. Many cause allergies and irritations that also need avoiding.

Tips on Dangerous Plants

• Don’t let children eat seeds and plants from the garden unless supervised.
• If you wish to see these types of plant take a trip to the Poison Garden at Alnwick which also includes strychnine opium and cocaine plants under a special Home Office license.

• Be sensible don’t cook with these plants and take care around the garden.

Highly Harmful plants and flowers

Aconitum – Monkshood	Mandragora – Mandrake
Arum – Cuckoo pint	Nerium Oleander – Oleander
Belladona – Deadly nightshade	Oenanthe Crocata – Dead mans fingers
Datura – Angels Trumpet	Phytolacca – Inkberry, Pokeweed
Colchicum – Autumn Crocus	Ricinus – Castor Oil plant
Convallaria – Lily of the valley	Ruta – Rue
Dieffenbachia – Dumb cane	Scopolina
Digitalis – Foxglove	Solandra – Chalice vine
Euphorbia – Spurge	Solanum Dulcamara – Woody nightshade
Heracleum – Hogweed	Sophars – Pagoda tree
Hyoscyamus Niger – Henbane	Taxus – Yew
Laburnum	Thevetia – Yellow oleander
Lantana – Shrub verbena	Zigadenus – Death camas

On a lower scale of danger are many other plants that you would do well to avoid eating. Lupin seeds, Hellebores and Hyacinth even Swiss Cheese plants can cause problems such as swelling of the throat, vomiting, dermatitis, heart and digestion problems (enough I say lets grow some nice fruit and veg).

Wicked Plants: The A-Z of Plants That Kill, Maim, Intoxicate and Otherwise Offend by Amy Stewart

Photo Credit
Castor oil plant in August by pcgn7 CC BY-NC 2.0 Seeds are the source of the notorious poison ricin, best known for its use in the assassination of Bulgarian dissident Georgi Markov in a London street.